But Collins, in a statement explaining her decision to oppose Pitlyk, questioned if Trump's pick would be able to separate her personal views from the rulings she will make as a judge.

"My concern is not based on Ms. Pitlyk’s personal views on abortion or various medical decisions, which she has every right to hold. I do question, however, given her pattern of strident advocacy, whether she could put aside her personal views on these matters," Collins added.