PORTLAND, Maine (AP) — It might be a while before a winner is determined in the most expensive Congressional contest in Maine history, and when the winner emerges, he may well have set another precedent: The race looks as if it could be the first time a member of Congress is elected by way of a ranked-choice ballot.

Only a few hundred votes separated Republican U.S. Rep. Bruce Poliquin and Democrat Jared Golden as results trickled in early Wednesday, with both short of the majority one would need to avoid triggering an unprecedented re-scoring of ballots.

A slim chance remained that either could secure enough votes to avoid that scenario.

Maine used ranked-choice ballots for the first time in primaries earlier this year and is the only state to do so. The system lets voters rank candidates on the ballot with provisions for candidate eliminations and additional tabulations. It's also used in about a dozen municipalities around the country.

The ranked-choice system comes into play only if no one wins a majority of first-place votes, and that looked like it could be the case in the 2nd District race, in which independents Tiffany Bond and Will Hoar were also running.

If the race does go to a ranked-choice decision, final tabulations would be done next week.

Also on the ranked-choice ballot were re-election bids by Democratic Rep. Chellie Pingree and independent Sen. Angus King. Both won without the need for the runoff.

Poliquin, a two-term representative, was looking to defend his seat against Golden in a closely watched race that attracted lots of spending and heated rhetoric. The race featured saturation television ad campaigns and Poliquin and Golden calling each other liars.

Golden, a state representative and U.S. Marine Corps veteran, highlighted his military service while accusing Poliquin of trying to take away Mainers' access to affordable health care, pledging to create jobs and promising to protect gun rights.

Poliquin, elected in 2014, touted the state's low unemployment rate and his efforts to cut taxes and press for fair trade deals.

He called Golden "a young radical with a socialist agenda" in an attempt to portray him as too far left for the district, which handed an electoral vote to Donald Trump in the 2016 presidential election.

Financial disclosure reports showed that Golden raised five times more money than Poliquin in the quarter that ended three weeks before the election. It was the most expensive congressional race in the history of the state.

No challenger has defeated an incumbent in the district in more than 100 years.

In the 1st District, Pingree beat back a challenge by independent state Rep. Marty Grohman and Republican Mark Holbrook.

In the Senate race, King survived a challenge by opponents on his ideological right and left. King, a popular former Maine governor, faced Republican state Sen. Eric Brakey and Democratic activist Zak Ringelstein.

King caucuses with the Democrats and was first elected to the Senate in 2012. During the race, Ringelstein charged that the Democratic establishment abandoned him despite his winning the nomination.


Associated Press writer David Sharp contributed.


For AP's complete coverage of the U.S. midterm elections: http://apne.ws/APPolitics

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