WASHINGTON » The Democrats’ widespread losses last week have revived a debate inside the party about its fundamental identity, a long-running feud between center and left that has taken on new urgency in the aftermath of a disastrous election and in a time of deeply felt economic anxiety.

The discussion is taking place in post-election meetings, conference calls and dueling memos from liberals and moderates. But it will soon grow louder, shaping the actions of congressional Democrats in President Barack Obama’s final two years and, more notably, defining the party’s presidential primary in 2016.

"The debate will ultimately play out in a battle for the soul of the Clinton campaign," said Matt Bennett, a senior official at Third Way, the centrist political group.

Hillary Rodham Clinton, should she run, will face tension between the business-friendly wing of the party that was ascendant in the economic boom during her husband’s administration and the populism of Sen. Elizabeth Warren, D-Mass., that has gained currency of late.

"I want her to run on a raising wages agenda and not cater to Wall Street but to everyday people," Richard Trumka, president of the AFL-CIO, said of his expectations for Clinton.

Straddling the two blocs could prove difficult. Progressives have been emboldened to criticize party leaders after the Republican rout, particularly given a lack of a coherent Democratic message to address the problem of stagnant wages.

Sifting through returns showing that lower-income voters either supported Republicans or did not vote, liberals argue that without a more robust message about economic fairness, the party will continue to suffer among working class voters, particularly in the South and Midwest.

Obama’s wide popularity among activists and his attempt to transcend the traditional moderate-versus-liberal divide have largely papered over Democratic divisions on economic policy for the last six years. The party was also brought together by passage the health care law, a goal of Democratic presidents since Harry Truman. But with Obama’s popularity flagging, and an economic recovery largely benefiting the affluent, Democrats are clashing anew.

Unlike the 1980s, when heavy losses prompted moderates to plead with the party to move away from liberal interest groups and toward to the middle, it is now progressives who are the most outspoken.

And they are seizing on the election results to reorient the party. "Too many Democrats are too close to Wall Street, too many Democrats support trade agreements that outsource jobs and too many Democrats are too willing to cut Social Security — and that’s why we lose elections," said Sen. Sherrod Brown, D-Ohio.

Brown said he had talked to more than 60 Ohio Democratic leaders and activists since they got trounced in every statewide election and saw their state chairman quit. "The message I heard from all of them was: the Democratic Party should fight for the little guy."

To help provide a bridge to liberals, Senate Democrats on Thursday named Warren as part of their leadership.

While overwhelmingly in sync on the substance of cultural issues, some of the populists believe Democrats placed too much emphasis on such matters and not enough on economic fairness, depressing voter turnout.

"Gay marriage, abortion and birth control are important," said Terry O’Sullivan, president of the Laborers International Union. "But people join our organization for their livelihood, and that’s what our people vote on: their economic self-interest. I do think the party needs to re-examine what it stands for and get back to bread-and-butter issues."

Labor is having its own struggles, with membership declining and Republican-controlled states moving to limit union power. Democrats lost crucial races in part because of their candidates’ struggles in traditional union enclaves like eastern Iowa, suburban Detroit and parts of Wisconsin.

For example, in losing to the Republican they perhaps most wanted to beat, Gov. Scott Walker of Wisconsin, unions saw their members’ turnout slip. After making up 32 percent of all voters in the 2012 recall attempt against Walker, union households made up just 21 percent of the Wisconsin electorate last week.

Part of that drop is a result of Walker’s pushing through changes to collective bargaining law that thinned the ranks of his state’s union members. But what exasperates some labor leaders is that Mary Burke, the Democrat who tried to unseat Walker, would not even commit to undoing the changes that have crippled unions.

Echoing many liberals, Steve Rosenthal, a longtime Democratic strategist with ties to labor, said progressive organizations and unions should become more engaged in primaries and push candidates to stand for their agenda just as the right tries to make Republican candidates hew to conservative orthodoxy.

"I think it’s critical for folks on the left to do more of the same," Rosenthal said

There were a handful of bright spots in an otherwise dismal year for Democrats, and progressives are holding up as models the success of three Senate candidates who ran as populists: Sen. Al Franken of Minnesota, Sen. Jeff Merkley of Oregon and Sen.-elect Gary Peters of Michigan.

Merkley won by 19 percentage points with a campaign centered on the loss of well-paying jobs, the spiraling cost of college tuition and his opposition to trade deals that he said send jobs overseas. While Democrats nationally were losing whites without a college degree by 30 percentage points, Merkley narrowly carried that bloc of voters.

"We didn’t lose them here in Oregon because we talked about what they care about," Merkley said.

But some center-left Democrats believe that this is the exception and that the party should give up on winning a majority of such voters.

"Slowly and steadily since 1968, culture has trumped economics with voting and the white working class," said Kenneth Baer, a former Obama administration official who has written a book on modern liberalism. "It’s become the great white whale for a shipful of Democratic strategists. Obama proved that while we cannot get wiped out with that demographic, the future of the coalition is among growing parts of the electorate which are neither white nor working class."

The question of which voters to pursue captures the party’s broader debate about its agenda. Centrist Democrats have chalked up the party’s losses to an insufficient performance among moderate and middle-class voters.

"We talk about policies helping the middle-class, but the ones we promote the most are ones that don’t speak to the middle-class, like raising the minimum wage," said Al From, who founded the moderate Democratic Leadership Council in the 1980s to counter the party’s move to the left and helped propel Bill Clinton to the White House in 1992.

Many liberals believe the disconnect between the politics of the party’s grass-roots and the message they hear from Democratic administrations has left blue-collar voters unenthused. "We do not have to struggle for an agenda that connects with working-class voters," said Rep. Rosa DeLauro, D-Conn. "We have an agenda that does that, but it does not get vocalized at the top."

Yet many progressives concur that simply pushing an increase in the minimum wage is an inadequate solution. Liberals want tougher restrictions on banks, more generous federal student loan aid, enhanced collective bargaining rights and a reassessment of the country’s trade policy.

Obama has made clear he intends to work with congressional Republicans to push for fewer restrictions on trade. Some union leaders said they intended to fight those efforts, and would be looking for an ally in Hillary Clinton.

"The next six months we’re going to be relentless on trade," vowed Larry Cohen, president of the Communications Workers of America. "I hope she comes to our side on this fight. The president is not starting out there."

Jonathan Martin, New York Times