Star Tribune staff writer

PHILADELPHIA -- Gov. Mark Dayton and Rep. Keith Ellison spoke to a breakfast for delegates from Minnesota and Tennessee at the Democratic National Convention here and pleaded with backers of Sen. Bernie Sanders to work for Hillary Clinton and other Democrats down the ballot this fall.

It was another sign that despite the outward shows of unity -- including Sanders moving to nominate Clinton by acclamation at Tuesday's convention meeting -- Democrats remain concerned about whether they have unified the party going into the fall election.

Polls show a much tighter race than Democrats hoped or expected following a Republican National Convention that nominated celebrity mogul Donald Trump.

"I want to talk to the Bernie Sanders delegates," Dayton said, growing emotional as he evoked campaigns past.

"One of the reasons (Sanders) was so successful is that he sounds a lot like Paul Wellstone, and that's a high compliment," Dayton said of his late friend, who continues to be an icon in progressive Minnesota politics.

"I understand what it feels like. I remember when Paul died, the sense of loss, the sense of nihilism, you know, what matters? (Sen.) Strom Thurmond gets to live to 100, and Paul Wellstone doesn't make it to 60? Why God? What's the point?"

Dayton, who reminded the delegates he was the only Minnesotan to make Richard Nixon's "enemies list," implored the delegates: "Please, I'm begging you, Hillary Clinton may not be Bernie Sanders, but she's  a progressive and she's a heckuva lot better than Donald Trump."

"I can say with confidence, as (Wellstone) used to say, 'She's from the Democratic wing of the Democratic Party,'"Dayton said before leaving for a meeting with the Democratic Governors Association.

Ellison, who represents Minneapolis in Congress and was a key backer of Sanders before recently endorsing Clinton, gave a rousing address about the threat of Trump taking America back to an era before Civil Rights victories.

Ellison's mother, who grew up in Louisiana, was sent to boarding school because of threats from the Ku Klux Klan because her father was helping organizing black voters there, Ellison said.  

"If you think we live in a smart phone democratic society, and that we won't slide back into an ugly scenario, you are wrong," he said. "Many societies, the politics shifted in a nasty, nasty way."

"I'm not trying to scare you," he said, although fear undergirded his argument. "But read your own history book. We've never had someone like Donald Trump on major party ticket."

Ellison said that if civic participation, voting and volunteering are civil virtues, then apathy and a failure or refusal to vote are "civic sins."

The delegates will hear President Obama, Vice President Joe Biden, and Democratic Vice Presidential nominee Sen. Tim Kaine at Wednesday evening’s session.