Casino mogul Sheldon Adelson and his wife, Miriam, each wrote $10 million checks to American Crossroads, the super PAC founded by Republican political guru Karl Rove, in the closing weeks of the campaign.

The mega-contributions were among the more startling findings Thursday, as post-election reports from campaign committees rolled in ahead of a midnight deadline at the Federal Election Commission. 

The Adelsons' $10 million checks were written Oct. 19,  two days after the last pre-election campaign finance reports were due at the FEC. On Oct. 30, the Adelsons each wrote another check worth $1.5 million, bringing their grand total of giving to American Crossroads in the final month of the campaign to $23 million, or 61 percent of the group's contributions for the period.  And, as detailed below, the couple also gave generously to a number of other committees. They appear to have added some $38 million to their already jaw-dropping political contribution total, which now appears to be approaching the $90 million for the 2012 campaign. 

You can see the filings as they come in by surfing over to our recent FEC filings page. Just click on the image at right.

Before these reports, the most recent peek at who funded the groups came in mid-October. Recent filings also detail the continued outside spending in one 2012 race–an all-GOP runoff election for a House seat in Lousiana. Here's what the reports reveal:

• Freedomworks, a tea-party aligned super PAC, reported receiving $5.2 million in contributions from the Specialty Group in the final days of the campaign. The money brings the little-known company's total contributions to $10.6 million. Even before the latest round of campaign finance filings the group was the biggest corporate donor this cycle.

Specialty Group–which changed its name to Specialty Investments Group Inc. on Nov. 28–uses the Knoxville address of attorney William S. Rose. In a rambling statement released after the groups' first $5 million was disclosed, Rose vowed to never say where the money came from. "The business of Specialty Group is my 'family secret,' a secret that will be kept – as allowed by applicable law – for at least another 50 years," he wrote.

Freedomworks is still reeling from a messy split between chairman Dick Armey, who quit the group at the end of November, and President Matt Kibbe.

• Other $1 million-plus donors to American Crossroads: Homebuilder Bob Perry  gave $1 million while atomic waste entrepreneur Harold Simmons gave $3 million–his holding company Contran chipped in $1 million more. Houston Texans owner Robert McNair gave $1 million, as did Robert Rowling, who owns hotels, Golds Gym and a host of other businesses, and W. Ed Borsage of Quantlab Financial and Gary Heavin, founder of Curves International, the gym that caters to fitness conscious women.

In addition, Weaver Holdings, owner of Weaver Popcorn, chipped in $500,000. Rex Sinquefield, the Missouri Republican who showed state pols $21 million of his money, chipped in a conservative $100,000. 

Despite all the money thrown in its direction, American Crossroads logged one of the worst returns on investment among outside spenders in the 2012 campaign. 

• Local Voices, a super PAC that spent the bulk of its funds seeking a second term for President Barack Obama, reported $500,000 donations from a pair of Pritzker family members, Linda and Rosemary. 

Rosemary Pritzker, who lists her occupation as photographer, founded the super PAC. 

• Priorities USA Action, the super PAC that supported Obama, raised $15 million in the final weeks of the campaign, and ended up with $4.3 million in the bank as of Nov. 26.

Big donations came from three current or former executives at hedge fund Renaissance Technologies: $1.5 million from Chairman James H. Simons (who gave the PAC $5 million this cycle), $1 million from CEO Stephen Robert, and $1 million from Henry Laufer, who previously was chief scientist but described himself as 'retired' on filings. More big checks came from megadonor Fred Eychaner, who already gave $3 million to the PAC this cycle, and added $1 million more, and from Steve Mostyn, of the Mostyn Law Firm, who gave $1 million, bringing his donation total to Priorities USA to just over $3 million. The Laborers' International Union gave $1 million as well.

William Neukom, former managing partner of the San Francisco Giants, gave $500,000. 

• Hedge fund manager and mega-donor Paul Singer gave American Unity PAC $500,000, bringing his total contributions to the group to more than $2.1 million.

American Unity PAC, which promoted Republican candidates who favor marriage equality for gays and lesbians, supported just two winning House candidates.  

Singer, who invests for pennies on the dollar on defaulted government debt, recently got help from a House member the super PAC didn't support. Rep. Connie Mack, R-Fla., moved a bill through his committee for consideration in the lame duck session that would force the government of Argentina to pay as much as $3.5 billion to holders of its defaulted debt, USAToday reported. 

• Super PAC for America reported spending $1.5 million on ads–and $1.95 million on campaign overhead–between Oct. 1 and Nov. 26.

The group avoided filing a pre-election report by running all of their ads after Oct. 16, so the report received Thursday is the first disclosure of where the group's last-minute money came from. In all, $1.1 million went to opposing Obama and about $370,000 supported Romney.

The group is chaired by radio host Michael Reagan, son of late President Ronald Reagan. Campaign operative and pundit Dick Morris is chief strategist, according to superpacforamerica.com.

Unlike most PACs, much of the group's money came in smaller chunks–checks of $100 to $10,000. The PAC's biggest expense was fundraising. From Oct. 30 through Nov. 15, super PAC paid $1.7 million to Newsmax Media Inc., the conservative web site where both Morris and Reagan are columnists.

Besides traditional advertising, Newsmax sells email messaging to "opt-in subscribers" of a variety of email lists–including 435,000 subscribers to the DickMorris.com email list which "is represented exclusively by Newsmax Media." Filings don't specify how the money was spent.

The group didn't immediately respond to a message left with treasurer Nancy Watkins.

•  Restore Our Future raked in $22 million in 11th hour donations.

Adelson and his wife endowed Restore Our Future, the pro-Romney super PAC an additional $10 million dollars. That comes to $30 million from the Adelson's to Restore Our Future alone.

Other big name donors to Restore our Future including Bob Barker of "Price is Right" fame, who gave $174,000. Two sports team owners donated as well. Robert McNair, owner of the Houston Texans gave $1 million and Jeffrey Loria, owner of the Florida Marlins, gave $50,000.

Restore Our Future also received a $50,000 from an Ariane Dart who listed her occupation as homemaker, and provided no address. Ariane Dart is the name of the wife of Robert Dart, an heir to the Dart Container fortune who, along with his brother Kenneth, renounced his U.S. citizenship in the 1990s to avoid federal income taxes. A call to the Dart Foundation, where Ariane Dart is a board member, has not yet been returned.

Richard Mellon Scaife, the right wing billionaire who supported a slew of attacks on President Bill Clinton in the 1990s, also gave Restore Our Future $50,000.

•Adelson also gave $1 million to Hardworking Americans Committee, which bet and lost most of its money on the Republican Senate candidate in Michigan, former Rep. Pete Hoekstra. The super PAC registered with the FEC in late October, and kept its donors secret until it was required to disclose them Thursday. Adelson's last-minute donation makes up more than 80 percent of the total raised by the committee. Other major donations include $100,000 from Doug DeVos, president of controversial direct selling business Amway, and another $100,000 from Michael Jandernoa, president and CEO of Perrigo, a pharmaceuticals manufacturer.  

Adelson, who's vowing to double-down on his campaign giving despite his lack of success in 2012, also gave $2.5 million in the final weeks of the campaign to a super PAC attacking Tim Kaine, the Democratic candidate for senator in Virginia, according. Kaine beat out former Sen. George Allen by about 5 percent.The super PAC, Independence Virginia PAC, raised just under $5.2 million–though nearly all of it came from two megadonors: Adelson ($4 million) and Perry Homes CEO Bob Perry ($1 million). Adelson's contributions appear to have kick-started the super PAC; through Oct. 11 the group had raised $1.2 million and spent about $750,000 but starting on Oct. 12, when Adelson's first contribution arrived, the PAC began a spending binge that didn't end till election day.

Adelson is also the sole donor to the Hispanic Leadership Fund Action, and gave a total $380,000 to the group; half of the total was undisclosed before Thursday. The super PAC only spent to support Republican presidential hopeful Mitt Romney. And the Adelsons each gave $1 million on Oct. 29 to the Republican Jewish Coalition Victory Fund. 

• Hedge fund manager Robert Mercer donated $370,000 to Republican super PACs after the October filing deadline, bringing his total super PAC contributions to $4.4 million during the 2012 election. The previously undisclosed donations went to Republican Super PAC and Prosperity First, Inc., both of which were primarily financed by Mercer. The two groups supported three Republicans who lost on Nov. 6.

Mercer was an early supporter of Mitt Romney, donating $1 million to Restore Our Future in July 2011. He also gave $1 million to Karl Rove's super PAC American Crossroads and $600,000 to Club For Growth Action.

• Benjamin Suarez, owner of direct marketing company Suarez Corporation Industries, gave $335,000 to the super PAC Empower Citizens Network (ECN), which spent more than $300,000 to oppose President Barack Obama. The contributions from Suarez, who is the only donor to the group, remained secret until ECN filed its report with the FEC on Monday. Suarez and a number of SCI employees have been investigated by the FBI for possibly illicit donations to Republican candidates, including Rep. Jim Renacci and Senate candidate Josh Mandel, who lost in November. 

• Now or Never PAC, a right-leaning super PAC that spent $7.7 million on a handful of House and Senate races, raised $6.4 million from three dark money groups, new filings show.

Although the super PAC raised a total of $8.2 million, most of the money came in after Oct. 17, ensuring the identity of the donors wouldn't be known until after Election Day. The post-election filing, received Thursday, disclosed those late-October donors: $2.2 million from New Models, a group that has been active in other campaign giving, and $1.7 million from  the American Conservative Union.  Both are non-profit groups that, under tax law, don't have to disclose the sources of their funding. A third dark money group, Americans for Limited Government–which gave $1.95 million in September, added $600,000 in October.

The final filing also showed $800,000 more from retired index-fund innovator Rex Sinquefield, of Westphalia, Mo., bringing his total donations to the group to an even $1 milllion. Since 2008, Sinquefield's given more than $21 million in Missouri races, according to the Wall Street Journal. Sinquefield's political giving recently was the subject of a front-page story in the New York Times.

• Spirit of Democracy America, a super PAC that played an outsize role in electing moderate Republican state Rep. Paul Cook over a Tea Party Republican in a rural California House district, got another half million dollars from Charles T. Munger, Jr., its post-general election filing showed.  Munger's father, who is also named Charles, is legendary investor Warren Buffett's No. 2 at Berkshire Hathaway.

In all, Spirit of Democracy ended up receiving the vast majority of its $2.1 million in funds from the younger Munger. He also made a less successful political investment, failing to defeat a proposition championed by Gov. Jerry Brown that will increase taxes on the rich to pay for education. Munger gave more than $35 million to a committee that opposed Brown's plan. The rest of Spirit of Democracy's funding–$254,000–came from three Indians tribes: The San Manuel Band of Mission Indians, Morongo Band of Mission Indians and Santa Ynez Band of Mission Indians. The other House candidate backed by the group, former California Lt. Gov. Abel Maldonado, lost to Rep. Lois Capps, a Democrat. 

• About three weeks before the election, Sam Zell, billionaire chairman of the bankrupt media conglomerate Tribune Company, contributed $50,000 to the New Prosperity Foundation (NPF), a Chicago-based super PAC that spent $1.6 million supporting variious Illinois Republicans in House races, though it only supported one winning candidate. The Tribune Company is one of the largest media corporations in the U.S., operating 23 TV stations and a number of newspapers, including the Chicago Tribune and the Los Angeles Times. But the company is in a bankruptcy proceeding, brought on in part by the debt Zell took on to purchase it. Zell's contribution brings his total super PAC donations to $430,000, all to conservative groups, including a total of $100,000 to NPF. Zell had previously donated to the pro-Mittt Romney Restore Our Future and the Karl Rove-operated super PAC American Crossroads; he chipped in a final $25,000 to Restore Our Future just days before the election. NPF, which took $145,500 (mostly from Illinois donors) in the final weeks before election day, only supported one winning candidate, freshman-elect Rodney Davis.

• Government Integrity Fund Action Network, a super PAC that's cloaked the identify of donors by passing them through a related non-profit "social welfare" group, got $1.4 million more in secret money in the final few weeks before the election. Of $2.5 million raised this cycle, all but $10,000 has been from secret donors. The group spent $1.3 million supporting Republican Josh Mandel, who lost his race for Senate in Ohio, and $1.1 million opposing Democrat Elizabeth Etsy, who won her race for a Connecticut House Seat.

• The well-stocked super PAC End the Gridlock that unsuccessfully tried to get Bob Kerrey elected for a second tour of duty as Nebraska's senator had connections to very high-profile people. In its recent report, the group revealed that it raised $436,600 in the final weeks before the election. Its biggest late-in-the-game donors were New York private equity executive Vincent A. Mai ($100,000) and Baltimore Orioles owner Peter Angelos ($75,000), who has contributed at least $1.6 million to Democratic super PACs this cycle. Many of its donors come from big names in philanthropy and Democratic fundraising. They include billionaire Los Angeles philanthropist and former homebuilder Eli Broad ($10,000), co-founder of the private equity firm Blackstone Group Peter G. Peterson ($10,000), and M.K. Pritzker ($25,000), who is married to J.B. Pritzker, a billionaire heir to the Hyatt Hotel corporation and brother to Penny Pritzker, who was a major Obama fundraiser in 2008. Other donors to End the Gridlock included Twitter co-founder Evan Williams ($10,000) and the American Association of Justice PAC ($20,000), which represents trial lawyers.

• Super PAC spending is not over in at least one House race. In preparation for a Dec. 8 runoff between GOP Reps. Jeff Landry and Charlies Boustany, outside groups have spent $465,505 on independent expenditures since the election's first round took place on Nov. 6; 61 percent of it has been pro-Boustany. That's a slight reversal from the outside spending before Nov. 6, when pro-Landry outside groups spent slightly more than half of the outside money in the race. The main group on Boustany's side is Lousiana Prosperity Fund, a super PAC formed in August that has not yet reported most of its donors. On Landry's side is the libertarian super PAC FreedomWorks. However, the Boustany campaign had far more money in the bank than his opponent as of mid-November, Bloomberg News reported.