Republican Sen. Susan Collins of Maine said on Tuesday from the Republican National Committee convention in Cleveland that she hasn't ruled out voting for the presumptive Democratic presidential nominee, Hillary Clinton — an admission that shows exactly how unpopular Donald Trump is within the GOP establishment.

"Well, I have always supported the nominee of my party my entire life and it is extremely unlikely that I would vote for Hillary Clinton," Collins told CNN, adding, "But, I'm not completely closing the door but it is extremely unlikely. It is more likely that I would decide to write in a candidate or choose another approach." Collins has not shied away from criticizing Trump throughout the 2016 election season, which often included defending Clinton.



"I certainly was critical of Donald Trump when he accused Hillary of playing the 'woman's card,'" Collins told Time last month. "She's an accomplished person who is clearly qualified to be president. I do have a good relationship with her."

Collins is among several Republican senators who are struggling to lend their support to the presumptive Republican nominee, including Sen. Mark Kirk of Illinois who rescinded his endorsement of Trump, as did Sen. Lindsey Graham of South Carolina.

While Collins said she is more likely to write in a candidate, she hasn't completely denied Trump could get her vote, saying on Tuesday, "We still have a ways to go, and I do believe in redemption." But Collins has been calling on Trump to change his ways for some time.

"I would love to be able to endorse Donald Trump, but he really has to change the approach that he's taken," she told CNN last month. "If I were giving him advice, I would tell him he should own up to making mistakes. ... And he should stop insulting people."

