Collins joined six Republicans and every Senate Democrat to vote to convict former President Donald Trump last week.
The nurses union and the governor called the decision an insult to front-line workers and residents waiting for shots.
The Republican senator has won re-election against Democrat Sara Gideon.
Collins faced the toughest reelection bid of her career. Her win gives Republicans a key victory in their effort to maintain control of the Senate.
Some election experts say the state's unconventional voting system could spell trouble for the embattled Republican.
The Republican senator should apologize for dismissing "our concerns and our pain," said one Black Lives Matter activist in Maine.
The same brown-haired woman appears in political attack ads in Maine, Kansas and Iowa.
Experts say Maine's ranked-choice voting system could hurt the Republican senator's reelection chances.
The Christian Civic League of Maine supports conversion therapy and opposes gay marriage — and the Republican senator is thrilled to have its support.
The embattled Maine Republican joins senators Ted Cruz, Lindsey Graham and Mitch McConnell in the actor’s cartoon hall of infamy.