(Updated: 1/5; 11:15 p.m.)

As a fresh batch of lawmakers prepares to ascend Capitol Hill for the 114th session of Congress, some of the most effective outside groups in the last election are already seeing the fruits of their labor. The first priority of the Republican-controlled Senate will be to push for the long delayed Keystone XL oil pipeline.

The Sunlight Foundation has been tracking outside groups’ return on investment since November, showing the rate of success for the biggest super PACs and political nonprofits that played in the 2014 elections. Though the general trend has not changed since the day after the polls closed — wealthy Democratic donors lost big — a combination of recounts and runoffs kept us from knowing the final totals until recently.

In light of Republican Martha McSally’s recount victory over Rep. Ron Barber in Arizona, we have updated each of the group’s batting averages to reflect the final spending totals.

Click on “show candidate-by-candidate results table” to see the full spending breakdown by race.

Incoming Senate Majority Leader Mitch McConnell, R-Ky., has indicated that approval of the pipeline will be the first bill the Senate takes up, with a hearing and markup scheduled this week. House Majority Leader Kevin McCarthy, R-Calif., has told reporters his chamber will follow suit later this month. The House passed a bipartisan bill ratifying construction in the last Congress, and support for it has likely grown in the new one. So far, President Barack Obama hasn’t threatened to veto the bill, though some Democrats are urging him to do so.

A go-ahead on Keystone XL has been one of the premier issues for the U.S. Chamber of Commerce, the national trade group that routinely spends tens of millions of dollars on campaigns and lobbying. Like most groups that backed Republicans, 2014 was a banner year for the U.S. Chamber — 80 percent of its spending either supported winning candidates or opposed losers.

In September, the Chamber estimated the pipeline would create 42,100 new jobs, $2 billion in earnings and boost the national GDP by $3.4 billion.

Keystone has garnered support from labor unions that would see thousands of their members employed in its construction. The American Petroleum Institute, the voice of the oil industry, has been drumming up support for the pipeline across the country with heavy ad blitzes.

Just in time for the swearing in of the 114th Congress, another round of API advertising starts Tuesday in Washington, documents filed with the Federal Communications Commission and made available via Political Ad Sleuth reveal. A separate filing discloses that the subject of the ads is the Keystone XL pipeline.

Many of 2014’s large donors remain anonymous. Politically active nonprofit groups like Crossroads GPS and the Kentucky Opportunity Coalition dispensed major sums in last year’s political campaigns without ever having to reveal donors. But the Kentucky Opportunity Coalition’s ads on behalf of McConnell, citing Obama’s “war on coal,” suggest that some fossil fuel interests may have been behind the group.

Meanwhile, liberal campaign groups sounding the alarm on climate change and trying to ban “dirty” energy are not entering the battle from a tradition of strength.

NextGen Climate Action and the League of Conservation Voters (which also maintains a “dark money” arm) spent tens of millions of dollars on political ads but could not turn the tide that swept Democrats from their seats, weighed down by concern over the economy and an unpopular president. The LCV’s super PAC registered a measly 7 percent ROI.

No one person invested more fighting the pipeline than super PAC newcomer Tom Steyer, who pumped more than $70 million of his own money into his NextGen committee, which ran anti-pollution, anti-Republican ads in high profile Senate races across the country.

Despite spending over $19 million on election activities, the super PAC walked away from the elections with little to show for it. Republican candidates won the day in each of the marquee Senate match ups the group targeted. It finished 2014 with a lowly 32 percent success rate in the general elections.

Some Senate Democrats are hoping to amend the legislation. Politico reports that Chuck Schumer of New York and Debbie Stabenow of Michigan are rallying liberal allies to support amendments to the bill that would prohibit export of oil from the pipeline and provide more funds for federal green energy initiatives. Schumer, who opposes the pipeline and is a member of the Senate Democratic leadership, contends there are enough votes to uphold a presidential veto of the Keystone XL bill. It takes 67 senators to override a veto.

(Contributing: Jacob Fenton)