Presidential candidates Hillary Clinton and Bernie Sanders offered dueling messages highlighting the nation's stark income inequality, a unifying theme that emerged as they and other hopefuls appeared Friday in their first joint outing before hundreds of top Democrats gathered in Minneapolis for the Democratic National Committee's summer meeting.

Clinton, in a rousing speech punctuated by several standing ovations and chants of "Hillary!" told the crowd that, "Raising incomes and supporting families is the defining economic challenge of our time." Moving swiftly from one topic to the next, the former secretary of state proclaimed the Affordable Care Act "here to stay" and said that if advocating for equal pay and women's health "is playing the gender card, deal me in."

Sanders, the independent senator from Vermont who has drawn record crowds across the country, called for a "political revolution" that would bring the disaffected into the electoral process.

In his trademark simple but forceful speaking style, Sanders gripped the podium as he said, "that turnout, that enthusiasm, will not happen with politics as usual. The same-old same-old will not work."

Sanders also took an implicit swipe at Clinton, her party's front-runner. "We need a movement which takes on the economic and political establishment, not one that is part of that establishment," said Sanders, the one-time socialist mayor of Burlington, Vt., who was an avowed independent until he decided to run for the Democratic nomination.

He called for reform of criminal justice laws to reduce prison populations, campaign finance laws to limit the influence of the wealthy on elections, a move away from fossil fuels, and an end to what he called failed trade agreements.

Clinton and Sanders were the largest draws, but filling out the lineup were former Maryland Gov. Martin O'Malley and former Rhode Island Gov. Lincoln Chafee, both of whom have struggled to find support. Former Virginia Sen. Jim Webb had been scheduled to speak, but bowed out late, saying he needed to take his daughter to college.

O'Malley, the former mayor of Baltimore, used his time to argue that Democrats should welcome more debates before deciding on a nominee.

"The Republicans stand before the nation, malign our president's record of achievements, denigrate women and immigrant families, double-down on trickle-down, and tell their false story," O'Malley said. "We respond with crickets, tumbleweeds and a cynical move to delay and limit our own party debates." The DNC earlier this year set the number of debates at six — a move O'Malley has said was calculated to benefit Clinton.

Chafee touted his record in the Senate, statehouse and local government, saying he'd voted against the tax cuts pushed by President George W. Bush and opposed the authorization of the war in Iraq. Chafee at one point noted he had gone 30 years in public life without a scandal. "That's not easy in Rhode Island," he said.

Clinton's challenges

Clinton's challenge ahead of Friday's event was whether she could excite progressives and others within her party who have criticized her campaign as lackluster and overly cautious. That impediment has been underscored by Sanders' rising poll numbers and fundraising totals.

On Friday, delegate enthusiasm for her was evident, even as the former first lady's 30-minute speech ran over the allotted time. Clinton also sought to contrast her candidacy sharply with that of the 17 Republican presidential candidates.

"The party of Lincoln," she said, "is now the party of Trump.

"Not one of them had a single word to say about how to make college more affordable … no solutions for skyrocketing prescription drug costs. No promises to end the era of mass incarceration or say clearly and loudly, black lives matter," Clinton said of her GOP rivals, echoing the call of civil rights activists.

Minnesota Republican Party Chairman Keith Downey criticized Clinton and the other Democrats in town for their summer meeting.

"This is a disaster scenario unfolding for the Democrats," he said. "Hillary Clinton is crumbling; they know the concept of a Joe Biden candidacy is far better than its reality, and the only one generating enthusiasm is the socialist, Bernie Sanders."

Downey called his party's candidates "a direct contrast to the Democrats' East Coast, yesteryear field of candidates, all striving to lead their party's post-Obama socialist orthodoxy and its divisive politics."

For the Democratic candidates, Friday was their first chance to appeal directly to a national gathering of current and former elected leaders, state committee members and other party leaders who serve as super delegates in the presidential campaign. While the super delegates are not bound by any commitments made to a candidate before next summer's convention, they are highly sought after by presidential hopefuls.

E-mail controversy

On Friday, Clinton made it clear that she intended to woo her party top to bottom, pledging to help Democrats win up and down the ticket.

After her speech, Clinton told reporters that she has worked to earn the support of delegates and other key allies. She said Friday's response by DNC delegates "is more a result of the lessons I've learned in the past."

"I'm very encouraged by the kind of response I'm getting," she added.

Clinton's campaign continues to grapple both with continued questions about her private e-mail account and the possible entry of two-term Vice President Biden, who could pose a formidable threat to her position as front-runner for the nomination.

On the e-mails, Clinton told reporters — as she has in the past — "I did not send or receive classified material" via the private server.

Of Biden, she said, "I've got the greatest affection and admiration for the vice president. And I am not going to comment on differences or similarities. This is a difficult decision for him to make, and as I've said before, I want him to have the space and time to do it."

The summer meeting of the Democratic National Committee concludes Saturday.

The Associated Press contributed to this report.

Ricardo Lopez • 651-925-5042

J. Patrick Coolican • 651-925-502