PHILADELPHIA — At one of the many protests outside City Hall this week, Leisa Duncker sat in the blazing sun with a black Sharpie marker writing "Election Fraud" across her blue "Bernie Sanders" signs.
Duncker is a Sanders supporter from Florida — a swing state — and she's voting for Green Party candidate Jill Stein in November.
In front of Duncker, the leader of this "Occupy the DNC" event yelled into his microphone: "They must understand that we will never vote for Hillary Clinton."
"I hear many people saying a vote for Jill Stein is a vote for Donald Trump," said the speaker, an organizer with "Black Men for Bernie."
The Vermont senator made that argument onstage this week, with President Barack Obama echoing that message Wednesday night when he urged all Democrats to get behind the nominee.
"You’ve got to get in the arena with her, because democracy isn’t a spectator sport," Obama said.
For many Sanders' supporters, the choice is clear: They have to back their second choice in the Democratic primary — holding their noses if they have to — in order to defeat Trump. “The vast majority of Bernie delegates and certainly myself, we want to defeat Donald Trump. And we understand Hillary Clinton is the way to do that," said Jeff Cohen, spokesman for the Bernie Delegates Network, which represents about two-thirds of the Sanders delegates at the convention. Some Sanders supporters are taking their time getting to that point, while others — especially those outside the convention hall — say they will never be ready to fall in line behind Clinton.
Many of them are from blue states and openly admit that they can vote for Stein because their vote won't throw their state to Trump.
But others disregard the whole idea that supporting a third party candidate could boost Trump, or if it did, that it would really be a problem.
"We're not voting for Donald Trump," said Yvonne Finnegan, 59, of Albuquerque, New Mexico, who plans to support Stein. "If the DNC picked a flawed candidate, don't blame us."
She's not worried about what would happen if Trump won. "I don't think Donald Trump would affect me anymore than George W. Bush," she said.
And what about his effect on other people — Muslims, for example, whom he's proposed banning from the country? "I don't think he'll get away with anything," Finnegan said dismissively.
Others don't see much difference between Clinton and Trump. That's the case for Jameson Williams, 30, from Seattle. Neither candidate, he said, will take a strong enough stand on demilitarization, income inequality and the environment.
For a Clinton supporter like Texas Rep. Marc Veasey, that's a difficult position to understand.
"I can’t go into 2017 comfortable with me being a black person knowing that Donald Trump is going to be the president of the United States," the Democratic congressman said in an interview in Philadelphia this week.
"And I think that a lot of the Bernie Sanders people, they need to get to a place where it’s that critical to them also that Donald Trump can’t be president," he said.
Maine Rep. Chellie Pingree, whose state voted overwhelmingly for Sanders in the Democratic primary, acknowledged that it may take some time for Sanders supporters to get on board with backing Clinton as the only surefire way to defeat Trump.
"I’m hoping people see that over time, but I understand, you know, we’re still in the middle of this debate. We haven’t finished our own convention. So I think there’s a way to go before people all feel that way," she said.
The burden is on Clinton to bring disaffected progressives into her tent, Pingree said.
"They can’t expect people to just come into the fold just because," she said.
"Secretary Clinton has to get up there, she has to make the case, and she has to say over and over again how she’s going to embrace many of the items on his agenda, and how she’s going to do different things than people may be expecting," Pingree said.
But the Maine Democrat remains hopeful that Sanders supporters will become more comfortable with the nominee.
"A week is a long time in politics," she said.