Above Las Vegas last week, the air invisibly crackled with attacks and counter-attacks by candidates for a House and a Senate seat — not to mention President Obama, his rival Mitt Romney and their backers. In Denver, there was a clash of political fronts:  Outside groups like Planned Parenthood and Crossroads GPS competed for airtime with each other, as well as the candidates they are supporting.

In Grand Rapids, Mich., ads in a high-priced contest over a bridge to Canada dominated the TV airwaves, while in Sacramento, it was ballot initiatives and House races vying for voters' attention. Milwaukee viewers were inundated with ads by candidates for a host of offices – including one from the Paul Ryan for Congress committee (a reminder that the GOP vice presidential nominee is not above hedging his bets).

A heat map of the political air wars last week would have showed the most vivid spots around those cities, the five television markets where the wheeling and dealing by ad buyers was most intense.

This new and revealing campaign weather report is made possible by Political Ad Sleuth, a tool that the Sunlight Foundation is launching with a big assist from the media watchdog group Free Press, as well as journalists, journalism students and other civic-minded volunteers across the country.

Ad Sleuth collates the tens of thousands of political ad files now in the Federal Communications Commission’s online archive and makes them easier to search. It also gives citizens tools to help us expand and improve this groundbreaking database of political ads. More about how to accomplish both below. Meanwhile, a bit about what Political Ad Sleuth can help you do now, about what we hope it will enable you to do in the future and about why we are undertaking this effort and asking for your help this year:

What you can do with Political Ad Sleuth: You can search for political ad buys by state, by TV market, by name of the entity buying the ad (“Romney” or “Obama,” “Crossroads” or “Priorities.”) You can see the most recent ad buys. You can search for and find the documents that identify the principals behind a committee buying ads. And you can download a .csv file to further refine your explorations on your own.

What you can’t do (yet) with Political Ad Sleuth: You can't yet easily compute total ad purchases for a committee by TV market or a wider geographical entity. You can't yet connect a buy to a specific ad.

Why we think it is important to complete this project: This is the first presidential election to take place since the Supreme Court’s controversial 2010 decision in Citizens United. That decision paved the way for the formation of new kinds of political committees, thinly disguised as non-profit “social welfare” organizations, which can spend unlimited sums of money to elect or defeat candidates without so much as registering with the Federal Election Commission. That makes it hard to get behind anodyne names like “Americans for Better Apple Pie” to figure out what interests are trying to curry favor with our elected officials.

But there is one place where these mystery meat committees leave a paper trail: At local TV stations. Federal Communications Commission regulations require buyers of political ads to identify an officer of their group to the television station and require the local TV stations to make that document, along with other details of the ad purchase, available for public inspection.

Here’s an example of how you can take advantage of that requirement, using Political Ad Sleuth, to track down who's bombarding you over the airwaves:

This week, USA TODAY’s Susan Davis wrote an interesting story on “boutique PACs” that are focusing on individual House races, dumping in enough money to potentially be decisive. Davis highlighted one called Now or Never PAC, which has purchased $1.7 million worth of ads against Tammy Duckworth, the Democratic nominee in an Illinois House race. The group’s founders “do not have to be disclosed and remain unknown,” David noted.

Not to the FEC, that is. By searching Political Ad Sleuth for Now or Never, we quickly turned up an FCC-required document that identified the group’s treasurer as James C. Thomas III and its executive director as Jason S.M. Smith.

Thomas, according to this blog post from the Kansas City Star, last year served as treasurer of the Missourians for Equal Credit Opportunity, a front for the payday loan industry which was fighting a ballot initiative to limit the annual rate of a short term loan at 36 percent as opposed to the 1,950 percent currently allowed).Backers of the measure recently gave up an attempt to get it on the ballot this year.The writer of the post, Barb Shelley, said Thomas is associated with Jeff Roe, founder of Axiom Strategies and a former chief of staff to Rep. Sam Graves, R-Mo. Another Sunlight database, Influence Explorer, shows that so far this cycle, Thomas has given $1000 to Graves and $100 to Secure Arizona PAC, which he also serves as treasurer and which made $17,500 in independent expenditures against Rep. Jeff Flake, R-Ariz., this year in his successful effort to win the GOP Senate nomination.

Smith, Now or Never’s executive director, is a Texas political strategist and veteran of the Rick Perry campaign. His bio is here on a site that belongs to the apparent related It’s Now or Never PAC. It’s a super PAC that does file reports with the Federal Election Commission. However all of the $140,000 in donations to It’s Now or Never, super PAC come from the identically named Now or Never 501(c)4 – one of those non-profits that is not required to disclose donors.

It’s Now or Never spent a little over $2,000 backing Nevada state Sen. Barbara Cegavske’s unsuccessful effort to wrest the GOP nomination for the state’s new congressional seat from Danny Tarkanian, son of famed UNLV basketball coach Jerry Tarkanian. Having spent so little compared to what the group raised, this branch of It's Now or Never should have a significant war chest to make a difference in other races this year.

Such sleuthing was difficult to do until very recently because political ad files could only be viewed by going to TV stations in person, a process that would have made getting a handle on the money spent on advertising this year almost impossible given the thousands of stations involved.

This year, however, the Federal Communications Commission ordered online posting of the station's public files, including records of political ad buys. Thanks to a federal court ruling denying the broadcasters' request to delay enforcement of the order beyond this election, on Aug. 2 some 200 stations in the nation’s top 50 television markets began posting the records of political ad buys online.

While this is good news for political transparency it’s not an unalloyed victory: To improve its chances of winning its case against broadcasters, who have been battling online disclosure for more than a decade on the grounds that ot creates an onerous paperwork burden, the FCC created a no-excuses system: It's very easy for them to upload their files. But ease for the broadcasters means challenges for the public: The files are difficult to search. 

That's because what’s on file at the FCC are PDFs – images of unstandardized forms (every station can use its own) that can’t readily be analyzed by computer.

Moreover, as we’ve already told you, many TV stations and many television markets that will see large sums of money spent on political advertising this year aren’t covered by the FCC order. Among them: All of the nation's Spanish-language stations.

Complicating the situation: The local TV stations that many voters rely on for information about this election are reaping enormous profits from the political ad buys. Many of the broadcasting groups that own those stations have been leading the fight against online disclosure, working against the interests of their own newsrooms. Our Free Press partners have documented the perhaps not-so-curious lack of scrutiny that stations benefiting from the ad bonanza are giving to the political propaganda they air. Free Press is not alone in its concerns about TV stations being unwilling to bite the hands that are feeding them. Respected University of Pennsylvania political scientist Kathleen Hall Jamieson is cataloguing deceptive claims allowed on the air by television stations on FlackCheck.org.

Political Ad Sleuth aims to overcome some of these difficulties by:

• Making it possible to do rudimentary searches of the FCC files right now by using the electronic tags that are used to file the documents;
• Giving you the tools to help us enable more sophisticated searches and computations of ad totals by helping us enter the information on the FCC documents into a structured database. All you need to do is create a log in and password. (Or, if you are like some of us and have difficulty remembering one more password, just use your Twitter or Facebook account. We use the information only to identify users and keep our system honest. We won’t sell or otherwise pass on your information).
• Empowering you to help us expand our database by uploading files from television stations or television markets that aren’t covered by the FCC order. Wondering where they are? Zoom in on the map here to find markets that aren’t covered. But even if you live in one of  the "top 50" markets, you'll find many stations in your area that don't have to post their political files online because they aren't affiliated with one of the four major broadcast networks.   Find them by checking the list of the covered markets here. The “stations mandated” column will show you how many stations are exempt from the FCC order. Click on the name of the TV market to see which ones they are.

While 50 television markets are covered by the new FCC rule, 160 are not. The Wesleyan Media Project estimates that some 450,000 ads aired between Aug. 2 and Sept. 30 outside the top 50 markets — well over half of the political ads the group monitored. 

In Iowa, estimates through Sept. 23 had presidential ad spending at $30.1 million and counting. But not one of the stations that broadcast within state lines are required to upload to the FCC database. Four out of five of Wisconsin's markets don't have to upload their files, either,  which leaves out 70 percent of the presidential ads in the state. Outside of Milwaukee, the ad files are tucked away in manila folders, hidden in the basement room of TV stations across the state. Like in Iowa. Like in any station across the country not posting to the database. 

Nor are ad buys made before the FCC order took effect Aug. 2 required to be posted online. 

From a visit made in June to the four network stations serving Washington, we know before June 6, Virginia Senate candidate Tim Kaine bought up at least $2.5 million in ads to run in the last two months leading up to the election. This amount is by no means comprehensive, since there is a large gap between June 20 and August 2. The stations visited were in one of six markets that serve Virginia, four of which are not in the top-50 covered by the FCC's online posting order.

This is important. There's a lot going on that we won't find out about unless you help with the missing pieces. Democracy is a participatory sport. Get in the game. Become a political ad sleuth and help us shine some sunlight on the dark money in the 2012 election.