The senator spoke up after news broke on Friday (via The Hill) that the Department of Health and Human Services would interpret sex discrimination based on "the plain meaning of the word 'sex' as male or female and as determined by biology."
Collins tweeted her promise to fight the change just a day after it was announced.
"The Trump Administration's decision to eliminate protections for transgender patients is simply wrong. I'll work to overturn this discriminatory policy," Collins tweeted.
This change caused outrage among LGBT advocates as well as some lawmakers who considered the Obama-era changes to be necessary to facilitate appropriate treatment for LGBT patients.
According to some health advocacy groups, this policy could lay the groundwork for hospitals, doctors, and insurance companies to deny healthcare coverage to transgender and nonbinary patients, as well as women who have had abortions, according to The Hill.
The Health Department did, however, clarify "the substantive protections prohibiting discrimination on the basis of race, color, national origin, disability, age, and sex remain in effect."
The statement of support for LGBT rights comes as the senator is fighting to win in a tight Senate race against a Democratic competitor who is close to Collins in the polls.The longtime senator has held her place in office for more than 20 years. Her Democratic opponent, state House Speaker Sara Gideon, is appealing to the more liberal among her constituency.
Collins' fellow senator from Maine, Angus King, is Independent in party affiliation and replaced a Republican when he took office in 2013. That change would indicate a leftward trend among Maine voters.
Replies to Collins' tweet were primarily negative, with followers calling her out for what they considered to be inconsistent words and actions.
"In other words, you will be 'concerned'...Too little too late," said one poster, sharing a campaign infographic for Collins' Democratic challenger.
"What are you gonna do furrow your brow, and wag a finger?" queried another. "Keep your empty platitudes, Senator DoNothing. Your time is up."
Collins' departure from the president is one of several rifts that Trump has had with party members. Just days ago, the president called for the party to amend their platform. Trump called for the change despite an announcement from the GOP that they intended to leave the charter as-is for the time being.