The push to draft Elizabeth Warren as a presidential candidate displays the Democratic Party’s fault lines, but will it change the party’s track in 2016? (Manuel Balce Ceneta/AP)

Last week, in a coffeehouse in downtown Des Moines, a group of progressive activists launched an effort that they hope will change the 2016 presidential campaign and in the process upend the Democratic Party.

The gathering in Iowa, organized by MoveOn.org and backed by Democracy for America, was the opening of a grass-roots push to draft Sen. Elizabeth Warren (D-Mass.) to run for president. Its broader effect was to escalate the debate among Democrats about the party’s values, its message, its real constituencies and, most of all, how it can win elections in the post-Obama era.

That there is such a debate over the direction of the Democratic Party is without question, and the differences have become louder in the wake of the drubbing the Democrats suffered in the midterm elections.

What is in question is the degree to which the rising populist movement on the left can materially shape the party’s future. More specifically, absent some sign from Warren that she is going to run, can these Democrats successfully pressure Hillary Rodham Clinton, the party’s dominant prospective presidential candidate, to adopt much of their agenda?

To those who argue that the ideological splits within the party are overstated or mostly stylistic, the effort to draft Warren is a misguided enterprise. “There ­really isn’t a huge division in the party,” said former Pennsylvania governor Ed Rendell (D). “. . . I don’t think it’s anything like the tea party and the Republicans.”

Rendell, who two years ago criticized President Obama’s campaign for attacking Mitt Romney over his business record at Bain Capital, said he believes most Democrats share Warren’s opposition to a provision favorable to Wall Street in the recently passed spending bill, which she blasted on the Senate floor.

Those trying to encourage Warren to run in 2016 argue a different case. Anna Galland, executive director of MoveOn.Org Civic Action, said there are important policy differences that need to be aired before Democrats pick their 2016 nominee.

She cited issues such as how the party should address income inequality, who holds positions of power in the executive branch — a cause taken up by Warren when she opposed Obama’s nomination of investment banker Antonio Weiss as treasury undersecretary — and whether it is even possible for Democrats to have a discussion about expanding, rather than constraining, Social Security benefits. “We are not debating style here,” she said. “We are debating substance.”

The power of populism

Populist energy pulsates within the party to the point that Democrats cannot agree on whether it has become its dominant ideological strain. Sen. Sherrod Brown (D-Ohio), who has championed a populist message as much as Warren, said: “It’s a good, strong message, and it’s a message that she’s carried very well, and it’s a message that a number of us have put out there for a number of years, and it’s catching on. . . . I don’t think it’s there yet.”

But Gov. Jack Markell of Delaware, who comes out of the centrist Democratic tradition, said he believes the party has tipped in favor of Warren’s anti-Wall Street, populist message. “I don’t think there’s any question,” he said of a shift that he finds worrisome for the party’s future hopes of winning over independents and swing voters.

Jim Dean, who heads Democracy for America, said that until recently, the party had “regressed” on the relationship between business and government. “With the ascendance of Elizabeth Warren and the way she has built power for herself, we are seeing a lot of movement for the party to get back to its core values,” he said.

Warren has given no indication that she will become a candidate in 2016. Her advocates on the left take hope from the present-tense language she has used to disavow her interest — “I am not running for president,” she repeatedly told NPR’s Steve Inskeep last week — as a sign that her posture is not irreversible.

Officials at MoveOn.Org, which counts 8 million members, have said they will commit $1 million to the effort to draft Warren and will set up operations in states with early caucuses or primaries to stoke interest. Democracy for America will chip in $250,000. The groups will focus on organizing in other early-voting states and plan a national day of action in early February, about one year before the 2016 Iowa caucuses.

“The only way it will really happen is if there’s a massive grass-roots campaign that shows tremendous support for Elizabeth Warren across the country,” said Neil Sroka, spokesman for Democracy for America.

A Democratic leader from a battleground state, speaking on the condition of anonymity to offer a candid assessment, said he had strong doubts that the movement can reshape the 2016 campaign message. He sees no one with the political heft or following, short of a Warren candidacy, who could pose enough of a threat to Clinton to change what she otherwise would do and say.

Rendell was more dismissive of the movement’s potential strength, largely because of what he sees as the lack of differences within the party. “First of all, there has to be a leader of a movement, and there isn’t a good leader,” he said, adding, “If Hillary Clinton ran against Jim Webb or Bernie Sanders or Elizabeth Warren, they’d get 5 to 6 percent of the vote” in Pennsylvania.

However, Tad Devine, a strategist who played key roles in several past Democratic presidential campaigns, sees far greater potential for a populist uprising to galvanize the political dialogue. Arguing that the sense of economic discontent is widespread and that the hunger for a sharper populist agenda is genuine, he said, “If somebody gets up and delivers it with credibility, it’s going to resonate very powerfully in a way that’s not indicative of the party divisions today.”

Other Democrats agree that Democratic and Republican candidates alike will be looking to seize the issue of middle-class economic insecurity and that a presidential nominee dare not lose that debate. “The party that figures out the economic message around making prosperity more inclusive for all Americans is going to win this election,” said Bill Burton, a former Obama White House official and current Democratic strategist. “I really do think Republicans will be as attentive to that as Democrats are.”

Clinton competition?

What rankles many progressives is the possible absence of a genuinely contested battle for the Democratic nomination. If Warren stays out, it is not clear who would have the combination of message and political strength to make the race competitive.

At this point, the field is far from fixed. Sanders, the independent senator from Vermont, has a worldview that excites some progressives, and he has visited states with early contests as he deliberates whether to run. Webb, a former senator from Virginia, has formed an exploratory committee and has put economic fairness on the table as an issue, but he acknowledges the long-shot nature of his possible candidacy. Maryland’s outgoing governor, Martin O’Malley, has ties to both the centrist and progressive wings of the party and traveled the country this year in preparation for a possible campaign.

Devine, an adviser to Sanders, said bluntly that anyone hoping to advance the populist agenda in a possible run against Clinton has to be prepared to wage a serious campaign with all that entails. Half-hearted bus trips through Iowa and New Hampshire are not enough, he said.

“If you want this message to take hold with people, you have to challenge the front-runner in the nominating process in a real way, not a symbolic way, the way Gary Hart did with Walter Mondale” in the 1984 Democratic race, he said.

At this point, no potential candidate appears ready to challenge Clinton in quite that way. Even many of those urging Warren to run tip-toe around sharp criticism of Clinton or what she stands for.

“Our members have deep respect for Hillary Clinton,” Galland said. “The point here is to elevate the exciting message, the powerful track record, the inspiring vision of Elizabeth Warren. That’s our focus, not on anti-Hillary or anti-Bernie.”

Dean, of Democracy for America, said the same thing about his organization’s involvement in the draft-Warren movement. Notably, Howard Dean — whose 2004 campaign became the rallying point for the progressive grass roots and lives on today as DFA — recently announced his support for Clinton.

Bill Carrick, a California-based Democratic strategist, explained one of the reasons. Pent-up desire for a populist economic message is strong, he said, but many older progressives are conflicted because of their affections for Clinton and her husband, former president Bill Clinton.

“Generationally there’s a bunch of people who are very progressive, who essentially are in the baby-boomer world, who are very, very comfortable with Hillary,” he said. “Some of it is they consider the Clinton years successful, politically and economically. Some of it is she’s going to make history and be the first woman president.”

Asked about concerns among some progressives that Clinton will not have the kind of strong message they want, Ohio’s Brown said: “I don’t particularly share those concerns. I think Hillary’s got a good sensibility for working-class voters.” Later in the interview, however, he said of Clinton, “She’s going to have to show more independence from Wall Street.”

Populist sentiment causes Delaware’s Markell to worry that the party will appeal too narrowly in 2016. He argues that what Democrats need are a growth-oriented message and policies to go with it. “Economic fairness and inequity are important,” he said. “And increasing the minimum wage is important. We’ve done it in Delaware.” But he warned against getting “caught up in the rhetoric of fairness for the sake of fairness.”

Colorado Gov. John Hickenlooper survived a serious challenge in his reelection bid last month in a crucial swing state. The business-friendly Democrat sees Warren’s populism as “only part of the message” the party needs to adopt. Creating jobs, curtailing excessive regulation of small business and other strategies need to be part of it as well, he said.

“It’s not populist in the sense that we’ve got a slogan and we go out there and shout it to the beat of a drum,” he said. “But I think it’s part of the equation of this frustration of working people that the system is skewed against them.”

Clinton became a more populist candidate in 2008 after losing a string of contests to Obama and demonstrated her appeal to white, working-class voters. In preparation for a possible 2016 campaign, she has already invoked income inequality as a problem that must be addressed. But her rhetoric, except for what she later said was a mangled comment attacking businesses, does not have the edginess of Warren’s.

How strong that message will be if she faces only limited competition for the nomination is what worries liberal activists — which is why they are hoping to entice Warren to run or help elevate her standing even higher. How much strength there is in the progressive movement, and how Clinton weighs its significance, will not be known until she makes her expected announcement of candidacy.