Gov. Charlie Baker is the state's leading Republican, and at last night's first gubernatorial debate, his Democratic opponent laid heavy emphasis on the incumbent's party affiliation.

Challenger Jay Gonzalez, appearing with Baker on the debate stage alongside moderator Jon Keller of WBZ News, lambasted Baker's endorsement of fellow Republican Geoff Diehl, the conservative state representative running for the U.S. Senate against Sen. Elizabeth Warren. Baker's only ambition, accoridng to Gonzalez, is to improve how state government is managed, but that's insufficient with Donald Trump as President.

"To me, that's not good enough. We deserve more from our governor, particularly now, when we've got a federal government that's taken us backwards in so many areas," Gonzalez said.

Baker returned the fire in short order.

"My views on Donald Trump are quite well known. I didn't vote for him," Baker said. "I've made quite clear my view on many of his positions and many of his policies. And he's not running, I'm running for governor, not Geoff Diehl."

Baker had his chance at Gonzalez as well over the course of the one hour debate, challenging the former Deval Patrick-era budget director over his plan to tax university endowments exceeding $1 billion in order to fund spending on k-12 education and transportation infrastructure.

"I'm being honest about the fact that I'm going to ask the wealthy to pay more in taxes so we can do it. And it's a very clear choice people are going to have in this election," Gonzalez said.

Baker dismissed Gonzalez's plan, saying that much of that endowment income goes to scholarships for lower- and middle-class kids.

"And why we would take $565 million away from Harvard and, $200 million away from MIT, and very significant numbers away from other colleges and universities here in Massachusetts that use that money to fund the very kids we're interested in seeing get an education just doesn't make any sense to me," Baker said.

Gonzalez took on Baker's record investing in the MBTA and transportation systems without raising taxes, saying Baker's investments have only maintained the status quo of the aging system.

"I am not trying to become governor to manage the status quo. The status quo is not working for working families across the state and our transportation is the thing I hear the most about everywhere I go," Gonzalez said.

Baker said transportation systems have been ignored for decades and he's made improvements that will make the T reliable in the long-term.

"And it's not sexy stuff. It's signals and switches and third rail and tracks and the stuff that really makes a difference with respect to the system's ability to perform," Baker said.

Baker took the accusation in stride until Gonzalez characterized the Baker administration's spending on education as "small-ball, status-quo stuff."

"We've done a lot of really important and good things and I simply do not buy for a minute this notion that we've been a status quo administration," Baker responded.

With 46 Massachusetts State Troopers currently under investigation for payroll fraud, Gonzales attacked Baker's handling of the widening State Police scandal.

"Corruption is rampant at the State Police. There have been eight people indicted, three people who've pled guilty for crimes committed on Gov. Baker's watch," Gonzalez said.

Gonzalez has called for Baker to fire Colonel Kerry Gilpin, who Baker appointed to investigate reports that troopers falsified overtime pay resources. Baker said the charges so far are a result of his administration cracking down on the troopers.

"We discovered it, we pursued it and we ended it. And I think that's exactly how we should have performed," Baker said.

The pair will debate again October 17 on WGBH News.