Labor's massive voter turnout effort played a major role in helping President Barack Obama win Ohio, Nevada and Wisconsin, according to exit polls, and its leaders are now looking for a more liberal, pro-union agenda from the White House.
"There are things the president can do, and we'll be expecting that leadership from President Obama," AFL-CIO President Richard Trumka told reporters after the election.
Topping labor's wish list - for now - is a push to raise taxes on wealthy Americans and discouraging Obama from agreeing to any deal with Republicans over the looming "fiscal cliff" that cuts into Social Security and Medicare.
But unions are also pressing for new measures that might help boost their sagging membership rolls. New investment in infrastructure would bring construction jobs for trade unions. Immigration reform - and a path to citizenship for 11 million undocumented Latino immigrants - would create a vast new pool of potential union members. And new regulations could remove some obstacles to union organizing.
Business groups that have vigorously opposed efforts to help unions draw new members say they will keep playing defense.
"My primary concern is in the regulations," said Randel Johnson, vice president at the U.S. Chamber of Commerce for labor issues. "We are afraid that on employment issues, the administration will stay firmly to the left and follow the lead of the unions."
A new rule expected from the Labor Department would force companies to reveal relationships with so-called union-busting consulting companies even if the companies have no contact with workers. The National Labor Relations Board is expected to start work on a rule that would force businesses to turn over workers' phone numbers, emails and shift times to union organizers.
The Obama administration might even consider a plan that would give an advantage in bidding on government contracts to companies that offer workers a higher living wage and generous benefits.
Unlike four years ago, unions have not made passage of card-check legislation a centerpiece of their agenda. The long-stalled measure that would require companies to recognize a union once more than half its eligible employees signed union cards instead of putting the question to a secret-ballot vote went nowhere in Obama' first term, to the chagrin of many union activists.
Card check remains a dead end with Republicans in firm control of the House. Amy Dean, a former head of the AFL-CIO in California's Silicon Valley, said unions are being more realistic about what they can get.
"They are all about strengthening the right to organize within the confines of what's politically possible," Dean said.
Unions showed they still wield considerable political muscle, despite declining membership and having to spend millions fighting efforts in dozens of state legislatures to curb their bargaining rights or limit their political clout. About 11.8 percent of all workers belong to a union; in the private sector union membership is only 6.9 percent.
Exit polls show Obama won 58 percent of voters from union households, compared with 40 percent for Republican Mitt Romney. That margin rose to 60 percent in Ohio and 66 percent in Wisconsin, where 1 of every 5 voters comes from a union household.
"We did deliver those states," Trumka said. "Without organized labor, none of those would have been in the president's column."
Unions expected to spend big - more than $400 million - to help Obama and other union-friendly candidates at the federal, state and local levels. The country's largest public workers union, the American Federation of State, County and Municipal Employees, says it spent about $100 million while the Service Employees International Union says it spent $85 million.
But labor's election success hinged in large part on its extensive ground game. Thousands of volunteers made millions of personal contacts with union and nonunion voters. Labor also took advantage of new rules on super-PACs, funneling at least $77 million to the groups, according to the Center for Responsive Politics.
An analysis by the Sunlight Foundation, which tracks money in politics, found that unions and other Democratic-leaning groups were far more successful than outside conservative groups in targeting money toward winning House and Senate campaigns. The SEIU spent more than 70 percent of its funds on winners, for example, while Karl Rove's American Crossroads and its nonprofit affiliate had only a 6 percent success rate.
In addition to measures that may help increase union numbers, labor leaders are also expecting the Obama administration to issue more regulations targeting workplace safety. Proposed rules to protect workers from cancer-causing and lung-damaging silica, often found in the dust at construction sites and glass manufacturing operations, have languished at the White House for more than a year. The administration also has delayed new standards for combustible dust that can cause explosions.
Business groups have opposed the regulations, saying they overreach and would raise employers' costs by millions of dollars.
AP Polling Director Jennifer Agiesta contributed to this report.