An independent state lawmaker believes Maine’s new ranked-choice voting system will help his bid to unseat a popular Democratic congresswoman in the state’s 1st Congressional District.

Democrat-turned-independent Marty Grohman believes the voting system designed to reveal a consensus winner through ballot rankings and extra tabulations gives him a better chance of beating both a liberal Democrat, incumbent Rep. Chellie Pingree, and a conservative Republican, Mark Holbrook.

Maine Rep. Marty Grohman

Ranked-choice voting is going to be used for the first time in federal races in November after Mainers on June 12 turned back a legislative delay.

“This should be a classic opportunity for us to show what this moderate-minded election reform can do,” Grohman said.

This system works like this: A candidate who wins a majority of first-round votes is the winner. If there’s no majority, then the last-place finisher is eliminated, and that person’s supporters’ second choices are reallocated to the remaining field.

The system was used for the first time in modern history in a statewide primary in Maine on June 12.

Democrats Janet Mills, candidate for governor, and Jared Golden, candidate in the 2nd Congressional District, both emerged as primary election winners after capturing the most first-place votes.

But the candidate with the most first-place votes isn’t always the winner. And an analysis emailed to Grohman’s supporters this month shows how he could come from behind to win if Pingree fails to capture 50 percent or more of the first-round votes in November.

A spokesman said Pingree is approaching this election the same way she’s approached all of her previous elections: She’s working hard to earn Mainers’ trust.

“We are confident that, regardless of how the election is conducted or how far to the right her two opponents run, the people of the 1st District will recognize her work and convincingly re-elect her,” said Chris Glynn, her spokesman.

Political scientists don’t necessarily see the race unfolding the way Grohman’s campaign does. The conventional wisdom suggests that even with ranked-choice voting, challengers face uphill battles against incumbents in both of Maine’s congressional races and in the U.S. Senate race.

“It’s not going to have much impact in November because these races are pretty well set,” said Sandy Maisel, a political science professor at Colby College.

The use of ranked-choice voting would have created intrigue if it were to be used in the governor’s race, which features a Democrat, a Republican and two independents.

But the voting system won’t be used in the gubernatorial race or in state legislative races in November because of concerns that it runs afoul of the Maine Constitution.

In the 1st District, meanwhile, Grohman continues to see reason for hope, and his campaign got a boost from Republican Gov. Paul LePage last week. LePage said Grohman “is what Maine needs” and called him a “good man” who’s in politics “for the right reasons.”

“We’ve worked together on some stuff. We disagreed vehemently about others. That’s the great thing about being an independent. I’m able to work with anybody,” Grohman said.

Pingree has always won with a majority in the past, but a three-way race could cause her to dip below the 50 percent threshold, Grohman’s campaign believes. If so, then Grohman expects to pick up enough second-choice votes from Republican Holbrook to put him over the top in November.