Gov. Charlie Baker today said he won’t back Donald Trump if the real estate tycoon wins the GOP presidential nomination, becoming the latest Republican to definitively split with the party’s frontrunner.

“I said I wasn’t going to vote for Trump yesterday and I’m not going to vote for him in November,” Baker told reporters at a North Andover elementary school, where he earlier read to students.

However, Baker said, he believes another candidate could still win the party’s nomination.

“I’m not willing to concede with 35 states still to go that he’s going to be the Republican nominee,” Baker said. “I don’t know how (Democratic candidate) Bernie Sanders and his supporters feel today when people run around and say the Democratic nomination is over. I don’t think the Republican one is over either.”

Trump rolled to wins in seven state primaries yesterday, including a massive victory in the Bay State.

The vote created an awkward political position for the moderate governor — overseeing a Republican electorate that bucked his own choice for president — and has forced many in the GOP to decide whether to denounce the party’s own frontrunner or support a candidate many have repeatedly criticized. New Jersey Gov. Chris Christie — endorsed by Baker in the primary — last week endorsed Trump after months of scathing critiques.

Baker has not said who he voted for in the Republican primary, and today didn’t say definitively who he’d support, or vote for, in the case of a Trump nomination.

“I’m not much of a fan of Hillary Clinton, let’s put it that way,” Baker said when asked if he’d vote Democrat. He did not directly address a question of whether he’d hope for a third-party option.

Yesterday, Republican Sen. Ben Sasse of Nebraska vowed to seek “some third candidate” over Trump if he is the nominee versus Democrat Hillary Clinton. A House Republican, Rep. Scott Rigell of Virginia, also said yesterday he would never support “a nominee so lacking in the judgment, temperament and character needed to be our nation’s commander in chief.” And the party’s leaders on Capitol Hill — Senate Majority Leader Mitch McConnell and House Speaker Paul Ryan — took the unusual step of publicly speaking out on Super Tuesday on the flap over Trump’s comments about white supremacist David Duke.

Today, Baker — who has condemned many of Trump’s controversial comments, including a vow to ban Muslims from entering the U.S. — brushed off a question of whether Trump’s success puts him in a political bind.

“I think the voters who supported me supported me because they wanted somebody who was going to focus on the work and that’s what I plan to do — continue to focus on the work,” Baker said. “I think the rest of it to some extent, certainly is nationally important, but I think what the voters care about here is how I’m doing on the job that they voted for me to do.”

Baker also insisted the nomination battle has not yet been won.

“I would say if I was a Sanders supporters, or if I was Bernie Sanders or any of the Republican candidates, it would annoy me that people are deciding that this is over before more than half the ballots have been cast,” Baker said, referencing speculation that Clinton has all but assured herself of the Democratic nomination.