The race’s fourth and final debate centered around whether Senator Susan Collins, the Republican incumbent, was as independent as she claimed to be from President Trump.
Despite hopes for a blue wave, Democratic candidates in Minnesota, Maine and Michigan are facing local political headwinds and have struggled to open up clear daylight in the polls.
The race in Maine, which could decide Senate control, is testing whether there is still room for Ms. Collins’s brand of moderation during a sharply polarizing presidency.
Senator Susan Collins of Maine has cultivated a reputation as an independent-minded Republican who delivers for her state. As she seeks re-election, she faces a growing set of political challenges.
Senator Susan Collins, a Republican, and her Democratic challenger, Troy Jackson, disagreed over the war in Iran and President Trump in the third of four debates in a key race.
An executive with the Republican super PAC that paid for the ad attacking Troy Jackson, the Democratic Senate candidate in Maine, blamed its vendor for running the ad in Oregon.