Not very many states share the history Maine has with policymakers outside the major parties. It currently has 7 voting members in the state legislature not affiliated with the Republican or Democratic Party, it has elected independent governors, and has one of the nation's only two independent U.S. senators.

Among the sitting independent legislators is Marty Grohman. Grohman is serving out his second term as a member of the Maine State House. Instead of seeking re-election, however, he decided to run for Congress in Maine's 1st Congressional District.

Grohman, a former Democrat, dumped his party affiliation in September 2017, and announced his independent congressional run in April.

Grohman and I spoke at the first-ever Unite Summit. He explained that 45 percent of district voters are registered unaffiliated, but have no representation in Congress. He says he plans to change that.

"I sum up my campaign in 5 words: 'Not a party line voter," he said in our one-on-one conversation. "That is what people are looking for."

There are three candidates in the November election for Maine's 1st Congressional District: Democrat Chellie Pingree (the incumbent), Republican Mark Holbrook, and Grohman.

In previous elections, a three-person race would create a nearly impossible scenario for a candidate outside the major parties to win. Independents and third party candidates are generally treated as spoilers in much of the US who just take votes away from one of the two major parties.

However, the 2018 congressional races will be different in Maine. Gone is the choose-one voting method that causes issues like vote-splitting. Maine will make history by being the first state to use an alternative voting method -- ranked choice voting -- in the November elections for US House and Senate.

Under ranked choice voting, candidates rank each candidate by preference. If no candidate gets over 50 percent of the vote in the first count, instant and automatic runoffs are held (eliminating the last place candidate after each runoff round) until a candidate reaches the majority threshold.

READ MORE: How Does Ranked Choice Voting Work?

Ranked choice voting changes the game in elections with more than two candidates, and Grohman welcomes the reform:

"This is what ranked choice voting is built for, a race like mine with someone in the middle -- like myself -- and a very left and a very right candidate. So nobody has to say, 'I would vote for the moderate -- I would vote for the independent, but I don't want the Republican to win.' Or say, 'I would vote for Marty, but I don't want the Democrat to win.'" - Marty Grohman

He added that ranked choice voting is a reform that delivers for moderates.

Grohman doesn't believe that his campaign strategy is any different in 2018 than it would have been in previous elections. The difference, he says, is that voters can feel confident in voting for the person they think is right, rather than against the person they oppose most.

Maine's 1st Congressional District is rated D+8 (likely Democrat) by the Cook Political Report. While this might sound like a clear win for the Democratic incumbent, the new voting system changes the way we need to look at these elections.

Grohman is a two-term state legislator -- a former Democrat, who has name recognition in his own district. His website touts a bipartisan record that has earned him the ranking of most bipartisan legislator, and the title of "Legislator of the Year" by both the Maine Retail Association and the American Legion.

In previous interviews, he has said he wants to take this bipartisan approach to Washington -- citing the enormous challenges that Congress is failing to address and growing voter frustration.

Tapping into that voter frustration and showing voters there is an alternative to politics-as-usual may be key to Grohman turning the 1st Congressional District into a much more competitive race than traditional models show.

This is not just a race for a voter's first choice, it is a race for their second choice as well. Denying the incumbent enough votes from her own party and outside her party would give the independent candidate a potential path to victory.