KEN THOMAS
Associated Press

WASHINGTON (AP) — Massachusetts Sen. Elizabeth Warren told a group of young Democrats Wednesday that the political system was “rigged” by powerful lobbyists and the wealthy and made an impassioned case for reducing burdensome student loans. Vice President Joe Biden said he had been on the front lines of debates over income inequality, climate change and gay marriage.

“I’ve been at the center of most progressive battles for a long, long time,” Biden said, in a lengthy speech to Generation Progress. He heard shouts of “We love Joe,” as he exited the stage.

Hillary Rodham Clinton remains the dominant figure in Democrats’ early 2016 discussions but she is beginning to get elbowed by liberals in her party as she considers a second run for the presidency. Potential 2016 rivals like Biden, Warren and Maryland Gov. Martin O’Malley are in the middle of a summertime tour of Democratic constituencies, frequently appealing to liberal activists who want a more populist approach to the economy and question the deporting of an influx of immigrant children from Central America.

Clinton, who dominates early 2016 polls, may avoid a significant primary challenge if she runs for president. Biden has kept all options open, Warren has repeatedly denied interest, while O’Malley promotes his record in Maryland as a model in the party and is actively exploring a campaign. But the jousting shows an inteest in an alternative, and preparations in the event Clinton doesn’t run.

“Ongoing current events give her potential opponents an opportunity to position themselves in contrast to her,” said Democratic strategist Tom McMahon.

Biden, who will address the liberal Netroots Nation conference in Detroit later this week along with Warren, noted his role as a leading advocate for President Barack Obama’s agenda in a wide-ranging speech that touched upon issues like domestic violence, voting rights and the problems of corrosive politics.

Biden said he’s often referred to as “middle class Joe,” telling the students that the economic bargain of years past had been broken and needed to be restored.

“Folks in the middle, they need to be cut into the deal, not cut out,” Biden said. “The folks at the bottom need to know that they have the chance to climb the ladder.”

Biden has maintained ties to the early voting states of Iowa, New Hampshire and South Carolina and projects a blue-collar image in contrast to the former first lady’s recent stumbles over discussions of her family’s wealth.

Warren has become a hero of the party’s economic populists, railing against high student loan debt at a time when Clinton has received six-figure speaking fees on college campuses. She passes them along to her family’s foundation.

In her speech, Warren detailed “how Washington is a rigged game” and said her bill to help students refinance their college loans at lower rates had been blocked by Senate Republicans and she cast blame on Senate Republican leader Mitch McConnell, R-Ky.

“Our voices matter and it’s time to use them. Together that’s how we make sure that our government works,” Warren said.

Warren has turned into a go-to surrogate for Senate candidates, campaigning for Democrats in Oregon, Kentucky and West Virginia. She planned to raise money for Rep. Gary Peters, who is seeking Michigan’s open Senate seat, during her trip to Detroit for Netroots Nation and was ending the week in Los Angeles at the National Council of La Raza, where immigration will be a leading topic.

Democrats note that Clinton still holds a sizable advantage in early primary polls and suggest she could appeal to all wings of the party. “The view among a lot of progressive people is that there’s a more practical view of her candidacy, there’s enormous strength there,” said Tad Devine, a veteran of Democratic presidential campaigns.

O’Malley has made trips to Iowa and New Hampshire in the past month and notably distanced himself from both Clinton and Obama on the crisis along the Mexican border.

“We are not a country that should turn children away and send them back to certain death,” O’Malley told reporters in Nashville, Tennessee, during a weekend meeting of the National Governors Association. Late Tuesday, reports of a leaked phone call between the governor and a top Obama aide surfaced, appearing to make O’Malley look like a hypocrite because he asked the administration not to send the immigrants to his state.

Clinton cited the need to reunite the children with their families but said during a CNN forum in June that the U.S. needed to “send a clear message: Just because your child gets across the border doesn’t mean your child gets to stay.”

During her book tour, Clinton has frequently cited the economic struggles of many Americans who have yet to partake in the recovery and pointed to the broad-based growth in jobs during her husband’s two terms in the White House. In an interview with German news magazine Der Spiegel, Clinton said the work of Thomas Piketty, the economist and best-selling author, showed that income inequality was “threatening to democracy.”

That message could help her connect with liberals, who have been wary of her ties to Wall Street and the corporate support of the Clinton Foundation. Liberals are closely watching how Clinton might frame an economic agenda in a potential presidential campaign.

“She has to figure out what’s her message for a new American electorate: African-Americans, Hispanics, young people, women, all of whom are suffering,” said Roger Hickey, co-director of the Campaign for America’s Future.

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