Savage, in an interview, said she approached the Gideon campaign with a proposal: both candidates would encourage their supporters, using the state’s atypical voting system, to rank the other as their second choice. She says the Gideon campaign declined to participate. And Savage is telling her supporters to rank Gideon second anyway, trying to block out the Republican senator.

“We really want to send the signal that we’re on the ‘get rid of Susan Collins team.’ We have no intention of being a spoiler for Sara Gideon’s bid,” Savage said. “Even though the Democrats don’t want to swap with us, we will go ahead and tell our followers: ‘if you want to, we’re going to suggest that you consider to vote blue number two.’”

Gideon’s had warm words for Savage and her spokesperson is encouraging her supporters to rank Savage second. But Savage's presence in the race is also a reminder of the ideological tension between Gideon, a favorite of Washington Democrats, and progressive Mainers that want candidates to embrace ambitious liberal ideas.

“The thing that’s been incredible to me is that I am the only candidate in the race calling for universal health care,” the progressive independent said. “I’m the only one calling for a Green New Deal…. The climate plan of the Democrat running in this race is pretty tepid and weak.”

Ranked choice voting, used in a handful of states, cost former Rep. Bruce Poliquin (R-Maine) his seat in 2018, and it could play a major role in the marquee Senate race. Gideon is generally leading Collins, but she’s rarely polling above 50 percent, meaning the ranked choice voting system could once again decide an important congressional race.

A poll this week from Colby College had Gideon leading with 46.6 percent compared to Collins’ 43.4 percent. Savage meanwhile had 4.7 percent while Independent Max Linn had 1.7 percent. The poll found that 37 percent of voters planned to rank Savage as their second choice, while 33 percent were unsure.

Professor Dan Shea, chair of Colby College’s government department, said that it’s likely that the race goes into ranked-choice and predicted that “Lisa Savage voters will likely pick the next senator from the state of Maine.” While he said voters’ choices are unpredictable because Linn and Savage voters dislike both major party candidates and polling for ranked choice involves small sample sizes, his research shows the ranked-choice system probably benefits Gideon more than Collins.

“The progressive voters will be more likely to move to Sara Gideon than the other two candidates. So I am rather sure that will be a big boon for the Gideon numbers in the end,” Shea said. “On top of that, Savage has pushed her supporters to support Gideon second in a modest but clear way.”

Savage’s call for her voters to support Gideon as a second choice could spell trouble for Collins’ bid, if most of the independent’s voters listen to her.

Savage, a teacher who has never held public office, argued in the interview that Maine’s ranked voting system will help Gideon “because most of the people in Maine lean Democrat not Republican.” The state has elected independents, Republicans and Democrats to the House, Senate and governorship over the last three decades.

“Many, many people have told me or shown their ballot ... that they ranked me first and they ranked Gideon second,” Savage said. “People that rank me first are very unlikely to rank Susan Collins second because our policies are so different. And people that rank Sara Gideon first are very unlikely to rank Susan Collins second.”

Maeve Coyle, a spokesperson for Gideon, had kind words for both Savage and the unusual voting system in a statement. Gideon also offered words of praise for Savage at a recent Senate debate, when asked what she admired about her competitors.

“Sara thinks it’s important for Maine, and the country, that Susan Collins and Mitch McConnell be replaced in the Senate,” Coyle said. “She has been impressed by Lisa Savage’s campaign, especially her bringing focus to the issues of health care and climate change, and would be proud to have her supporters rank Lisa second.”

But Savage’s voters could also opt to rank no one as a second choice, snubbing Gideon. And Collins could also benefit from voters who support Linn.

Annie Clark, a spokesperson for the Collins campaign, dinged Gideon for her response to the pandemic and cast the race as a clear choice between the two major party candidates.

“Our goal is to ensure that Susan Collins is the winner which is why we’re encouraging voters to choose her as their first choice,” Clark said.

In a debate this month, both Collins and Gideon said that they would accept the election results.

But Democrats are wary that Republicans could challenge the system far more effectively than Poliquin and potentially even topple the ranked choice voting system, which Maine voters approved in 2016, in part as a reaction to former conservative Gov. Paul LePage winning with pluralities.

“Collins has the resources to continue and take this all the way to the Supreme Court. We feel confident in ranked choice voting that we could win,” said Betsy Sweet, a progressive activist who ran against Gideon but now supports her. “But then we could lose ranked choice voting and then the race. I think that’s a scenario that people are not paying adequate attention to.”

Savage’s campaign has made ranked voting a key part of her long shot bid for the Senate. Her campaign manager Chris Cayer was the field director for two ranked choice voting campaigns, according to her website, and penned an op-ed in the Portland Phoenix this week pushing back on the suggestion that Savage would help Collins win a fifth term.

The ranked-choice system is an alternative that in theory should avoid clear-cut situations of a spoiler robbing a major-party candidate. And in close Senate races, it’s a very real possibility. Down I-95 a few miles, 4 percent of voters supported either an independent or Libertarian in New Hampshire’s Senate race in 2016, a battle Sen. Kelly Ayotte (R) lost by just 0.2 percent points.