Stein, a Lexington, Mass., physician, is attempting to position herself as a liberal alternative to Hillary Clinton, the presumptive Democratic nominee. A frequent candidate, Stein is again faced with little campaign cash, minimal name recognition, and daunting prospects of making an impact on the presidential race.

“We are coming together here outside of the DNC,” Stein told the crowd. “Inside the DNC they are looking for unity. They will not find unity inside the DNC, not with Hillary.’’

PHILADELPHIA — While delegates gathered in the Wells Fargo Center Monday for the Democratic National Convention, Jill Stein, the Green Party’s presumptive presidential nominee, and a group of her supporters took cover from a thunderstorm underneath a nearby highway overpass.


But Stein sees as an unprecedented opportunity in 2016 with supporters of US Senator Bernie Sanders — some of whom say they feel jilted by his support for Clinton. On the floor of the convention hall, Sanders supporters expressed their discontent throughout the opening day program, often disrupting proceedings with jeers and shouting.

Outside the convention hall, the rain began to pour minutes before Stein’s scheduled evening rally at a park nearby. As Mike Spera, 29, of Philadelphia, exited the park, he said he supported Sanders in the primary but now he’s seriously considering voting for Stein.

“Like Bernie, [Stein] is actually a liberal. It is not a complex thing,” he said.

Ernie Legg, 28, who traveled to the DNC from Rochester, N.Y., said Stein might be his only option.

“If there is no opportunity to vote for Bernie as a write-in or any other option, then [Stein] is the only viable option,” said Legg, who also attended the rally, wearing a Sanders hat.

But some Sanders supporters expressed hesitance about voting for Stein.

“I am not sure if I will vote for Stein or Hillary,” said Anya Willow, 40, of Brooklyn. “I guess it depends on what Trump says more than anything that Hillary or Stein or Bernie says.”


Sanders endorsed Clinton earlier this month — a move that some of his supporters saw as embracing the party establishment he has frequently criticized. In a recent interview at her home, Stein said she would have loved for Sanders to top the Green Party ticket, but he did not respond to requests from her campaign.

“I am not in this to establish my political career, and Bernie obviously brings a lot of experience and resources to the table,” Stein said.

Stein has waged two failed bids for governor of Massachusetts, and failed campaigns for secretary of state and state representative. In 2012, she ran for president, receiving just .36 percent of the popular vote.

She is mounting her 2016 campaign amid similar challenges: a limited campaign pocketbook, onerous ballot access laws, and criticism she might be a potential spoiler, someone who could steal votes from the Democrats.

Ralph Nader, who ran for president five times, twice under the Green Party banner, said though he believes Stein to be a person of “vigorous dignity,” he is not certain her efforts are much different than in 2012. She should be going directly to Sanders supporters and aggressively courting them, he said, because he believes she is still virtually unknown.

William Kreml, a former professor at the University of South Carolina and Stein’s strongest Green Party primary opponent, said in 2012 some Green Party members were not satisfied with her run. But now he said he sees “considerable improvement” in her organization and preparedness.


This year, Kreml estimated, it would be a victory to get 3.6 percent of the vote.

A Pew Research survey tracked the sentiments of Sanders supporters throughout the primary and found that 90 percent of his supporters would back Clinton.

When asked recently whether Stein could win the election, John Andrews, her deputy campaign manager, said, “It is clear that Hillary Clinton is the front-runner at this point.”

Unlike the major party candidate, Stein’s campaign does not have the bandwidth to open regional headquarters in every major city. Staffers are pouring much of their already limited campaign coffers into ballot access efforts, suing states and hiring petitioners to help gather signatures.

They’ve had their successes — for instance, they won a lawsuit in Georgia this spring, drastically reducing the required number of signatures to get on the ballot there. And according to Rick Lass, the campaign’s ballot access coordinator, Stein is on the ballot in 24 states as of late July, with a goal of doubling that number.

Stein’s campaign style is markedly different — and considerably more frugal — than her main party rivals. On the trail, Stein stays in the homes of supporters and volunteers, “taking trains and rides with other people, sleeping on couches and with dogs running around in rooms,” said anti-poverty activist Cheri Honkala, Stein’s running mate in 2012.


Stein also individually calls supporters, asking for their vote or campaign contributions. That’s what convinced Stephen Rollyson, 32, a software engineer from Georgia, to donate $1,000 to Stein’s campaign. “Honestly I was just flabbergasted a presidential candidate called me,” Rollyson said.

Lara Brown, an associate professor at George Washington University who studies elections and presidential aspirants, said Stein may pick up substantial support only if either Trump or Clinton are on track to clearly win the election, and voters feel like they aren’t wasting their ballot.

“Certainly Jill Stein I would imagine will be able to attract some of Bernie Sanders’ voters,” Brown said. “But at the end of the day whether or not people pull the lever for any third party candidate in the general election greatly depends on how close the election appears to be between the main party candidates.”

For Stein, that sometimes means reaching out to prospective supporters, one at a time. In the interview, Stein recalled a recent flight to New Jersey, when the man sitting next to her began complaining about the presidential field and lamenting Sanders’ loss in the Democratic primary.

If only he could find someone to vote for, he said.

“Oh really, let me introduce myself,” Stein said, extending her hand.

Globe reporter James Pindell contributed to this report. Meg Bernhard can be reached at meg.bernhard@globe.com. Follow her on Twitter @meg_bernhard.