President Trump’s Senate trial may have witnesses after all.

Sen. Susan Collins on Friday confirmed she is working with a “fairly small group” of fellow Republican senators to ensure witnesses can be called.

“We should be completely open to calling witnesses,” Collins (R-Maine) said Friday, the Bangor Daily News reported.

“I am hopeful that we can reach an agreement on how to proceed with the trial that will allow the opportunity for both the House and the president’s counsel if they choose to do so.”

Mitt Romney (R-Utah) has also had recent conversations with the Senate’s minority Democratic leadership, one source familiar with the negotiations told The Post on Thursday.

Democratic Senate leaders including Minority Leader Chuck Schumer (D-NY) are hoping that four GOP senators will break with their party and join Democrats in demanding certain witnesses.

Reps for Collins did not immediately clarify if the Republicans are working with Schumer.

Romney spokeswoman Liz Johnson denied he was working with Democrats — calling it “100 percent fake news” — but pointed to the senator’s public remarks this week that he is “comfortable” with the Clinton precedent of deciding on witnesses during the trial.

Collins revived the issue as House Speaker Nancy Pelosi on Friday ended her standoff with Senate Republicans without forcing a deal.

Collins and fellow moderate Sen. Lisa Murkowski (R-Alaska) appeared to side with McConnell this week on deciding on witnesses after the trial begins — as done during Bill Clinton’s 1999 trial.

In that instance, the Senate deposed but did not hear live testimony from Clinton witnesses, including Monica Lewinsky.

Murkowski’s office did not immediately say if she is among Collins’ group.

Republicans hold just 53 seats in the Senate. Fifty-one votes are needed to establish trial rules and call witnesses.

Democrats want to call witnesses including White House acting chief of staff Mick Mulvaney and former National Security Advisor John Bolton.

McConnell says Democrats had the opportunity during House impeachment proceedings, and that they cannot dictate Senate rules.

Some Republicans, such as Sen. Lindsey Graham (R-SC), firmly oppose calling witnesses, but Trump, impeached over his request that Ukraine investigate Democrats, has expressed interest.

Trump said Thursday, “I’m going to leave it to the Senate, but I’d like to hear from the whistleblower, I’d like to hear from shifty Schiff, I’d like to hear from Hunter Biden and Joe Biden.”

A McConnell spokesman did not immediately offer comment.