Washington CNN  — 

Republican Sen. Susan Collins, a key vote in the coming Supreme Court confirmation fight, said Sunday she would not support a nominee hostile to the landmark abortion ruling in Roe v. Wade.

“I would not support a nominee who demonstrated hostility to Roe v. Wade because that would mean to me that their judicial philosophy did not include a respect for established decisions, established law,” Collins said on CNN’s “State of the Union.”

The Maine senator said when she met with President Donald Trump to discuss the vacancy created by the retirement of Justice Anthony Kennedy, she encouraged Trump “to broaden his list beyond” his standing list of 25 potential choices.

Collins said she is not comfortable with everyone on Trump’s list of conservative names and stressed her preferences in their meeting.

“The President really was soliciting my views on the type of nominee that I was looking for,” Collins said. “I emphasized that I wanted a nominee who would respect precedent, a fundamental tenet of our judicial system.”

Trump told CNN at the outset of his campaign that he would use Roe as a litmus test for Supreme Court choices, and Vice President Mike Pence likewise said during the campaign that they would see the abortion ruling in the “ash heap of history.”

Nevertheless, Collins said Trump told her he would not ask a nominee how he or she would vote on Roe. She went on to say she did not believe Justice Neil Gorsuch, a conservative judge she voted to confirm last year, would vote to overturn Roe v. Wade either.

“I actually don’t,” she said of Gorsuch joining an opinion overturning Roe. “I had a very long discussion with Justice Gorsuch in my office and he pointed out to me that he is a co-author of a whole book on precedent.”

In addition to her belief on Gorsuch’s position, Collins also noted Chief Justice John Roberts previously expressed that Roe v. Wade had been established.

“I want a judge who will apply the law to the facts of the case with fidelity to the Constitution,” Collins said. “Roe v. Wade is a constitutional right that is well established, and no less an authority than Chief Justice Roberts said that repeatedly at his confirmation hearing.”

In a separate interview on the same program, Illinois Democratic Sen. Tammy Duckworth said she would advise her colleagues, including Collins and fellow key vote Sen. Lisa Murkowski, an Alaska Republican, not to “just trust that what somebody says to you in a conversation trying to get your vote is what’s going to happen when they are on the Supreme Court.”

“Justice Gorsuch told her that he would respect precedent, and yet he has voted against precedent just this week with the Janus case,” Duckworth said, referring to a labor union case decided Wednesday.

Democratic Sen. Maria Cantwell said in an interview on NBC’s “Meet the Press” that Democrats plan to stress the significance of replacing Kennedy, a frequent swing vote on the court, with someone who is like-minded on a host of issues, from Roe v. Wade to pillars of environmental regulations.

The Washington senator also anticipated hearing from Trump’s eventual nominee about key constitutional questions that concern the President himself, including the special counsel investigation led by former FBI Director Robert Mueller.

“Is the President able to pardon himself?” she asked. “Do you believe in the Emoluments Clause? … If the President is under indictment, what is that nominee going to do about that?”

CNN’s Maegan Vazquez contributed to this report.