Fredreka Schouten and Christopher Schnaars

USA TODAY

Labor scrambling to undo the 2010 election results in the states

Two major Republican donors died last year

Other GOP-aligned groups are likely to spend heavily in 2014

WASHINGTON — Labor unions and deep-pocketed donors promoting liberal causes are flexing their political muscle and have overtaken conservative billionaires in the race to fund super PACs, a USA TODAY analysis of new campaign-finance reports shows.

Nearly three dozen individuals and groups made donations of $500,000 or more to super PACs in 2013, pumping $62.6 million into these super-charged committees that can spend unlimited amounts to influence elections.

More than 87% of the money flowed from Democrats or donors backing liberal efforts, such as Keystone XL pipeline foe Tom Steyer, and big labor organizations, such as the AFL-CIO.

The early gush of liberal money underscores the high stakes of November's midterm elections. Democrats face a serious threat to their majority in the Senate, where Republicans need to net six seats to take control of the chamber. A Democratic super PAC focused on Senate races, the Senate Majority PAC, was among the big beneficiaries of liberal largesse, bringing in $8.6 million last year.

Democratic strategists expect to be outspent by conservative outside groups, such as Americans for Prosperity, and are moving quickly to build their campaign war chests to support a network of interconnected liberal groups. Americans for Prosperity, a non-profit affiliated with the billionaire brothers Charles and David Koch, had spent more than $24 million on ads slamming President Obama's health-care law through the end of last week. This week, the group announced a new round of ads targeting three Democrats.

Among liberal groups, the American Federation of State, County and Municipal Employees has pumped nearly $2.2 million into several closely aligned Democratic super PACs, including the Senate Majority PAC; the House Majority PAC, focused on House races; and American Bridge 21st Century, a super PAC digging up opposition research on Republican congressional and White House candidates.

"By pooling and combining resources, we can try to create a level playing field," said Brian Weeks, the union's political director.

Labor groups are marshaling their funds for this year's state battles in which 36 governors and a slew of state legislators are up for re-election. Big GOP wins in 2010 gave Republicans 29 governors' seats and control of both legislative chambers in more than two dozen states, helping spark a welter of legislation to limit union clout and to contain the cost of public-employee pensions as GOP officials sought to rein in budgets.

"We don't want to be as unprepared as in 2010," said AFL-CIO political director Michael Podhorzer. The union has moved nearly $2.4 million into super PACs and can spend millions more on outreach efforts to its members outside the campaign-finance system. "We're not leaving the federal field. It's important that Republicans not take control of the Senate," he said. "But every day, there is more damage being done at the state level."

Among the key targets for organized labor: Pennsylvania, where Republican Gov. Tom Corbett, has said he would sign a pending legislative measure that would end automatic payroll deductions from public employees' paychecks. Corbett is up for re-election this year.

No Republicans were among the top five super PAC donors in 2013, a departure from the previous year when a trio of Republican billionaires – casino magnate Sheldon Adelson, Dallas industrialist Harold Simmons and Houston home builder Bob Perry – dominated the list. Perry and Simmons died last year after donating a combined $2.1 million to conservative super PACs.

No super PACs reported donations from Adelson in 2013.

Instead, the California Democrat Tom Steyer tops the new list of super PAC mega-donors in 2013, pumping more than $11 million into his affiliated super PACs as the billionaire environmentalist seeks to make climate change a decisive issue in federal and state races, records show. (That total doesn't include an additional $8.5 million Steyer spent last year to help Democrat Terry McAuliffe win the governor's race in Virginia, a key presidential battleground in 2016.)

Chris Lehane, a senior adviser to Steyer, said the political team is spending the first few months of this year assembling its budget and plans for November. Don't expect Steyer to retreat, he said.

"The takeaway from 2013 is that you can use climate as a political wedge issue to both support those candidates who are willing to embrace climate and use it in a devastating way against those who adopt an anti-science position," Lehane said.

Steyer hasn't ruled out slamming Democrats, either. Sen. Mary Landrieu, D-La., up for re-election in November, is one of five senators who support the Keystone XL pipeline that Steyer's NextGen Climate group lists on its website as a potential target of a commercial.

In the No. 2 position among the big givers of 2013: former New York City mayor Michael Bloomberg, who gave most of his contributions to super PACs promoting his gun-control message. The Republican-turned-independent politician and businessman donated $2.5 million – more than a quarter of his super PAC giving in 2013 – to the Senate Majority PAC.

In all, the spending by the 34 mega-donors who contributed $500,000 or more to super PACs last year accounted for nearly half of the $136.1 million raised by all such groups in 2013.