Democratic gubernatorial candidate Jay Gonzalez seized Wednesday night on Gov. Charlie Baker's wavering over whether or not he will vote for Republican U.S. Senate candidate Geoff Diehl as Gonzalez attempts to dislodge the incumbent Republican from the corner office.

Diehl, a state representative from Whitman who is challenging U.S. Sen. Elizabeth Warren, became a centerpiece of a WGBH debate between the two gubernatorial candidates as Gonzalez tried to paint Baker as loyal to the Republican Party over the people of Massachusetts. Baker said during the debate that he hadn't decided whether he will vote for Diehl, but later told reporters that he misspoke and will cast a ballot for Diehl on Nov. 6.

At the midpoint of the debate, moderator Jim Braude asked Baker how he squares his opposition to President Donald Trump with his support for Diehl, who supports the president and helped organize his campaign in Massachusetts. Baker reiterated that he had pledged to support the whole GOP ticket and is supporting Diehl because he is part of that ticket.

But Gonzalez jumped in and had his own question for the governor. "Are you going to vote for Geoff Diehl?" he asked.

Baker responded, "I'm going to vote for me and I'm going to vote for Karyn Polito and I'm going to vote for a series of other candidates as well." Pressed on whether he will vote for Diehl, Baker said, "I haven't made a decision."

Gonzalez pounced and questioned how Baker could ask the people of Massachusetts to vote for Diehl without knowing whether he was going to vote for him as well.

"To me, this comes down to clear loyalty for the Republican Party over supporting issues like pro-choice and women's rights and LGBT issues," Gonzalez said.

After the debate ended, Baker told reporters that he got caught up in the back-and-forth and had misspoken.

"I said I was going to support the ticket, I'm going to vote for the ticket," he said. He added, "In the back and forth I simply misspoke but I'm going to vote for the ticket and I think it's interesting that my opponent spent so much time talking about the U.S. Senate race and so little time talking about the race for governor, which is the office he's actually seeking."

Gonzalez, during his post-debate time with reporters, suggested that Baker's change of heart came after huddling with political advisers and wasn't a genuine opinion.

"He can't have it both ways. He can't say he is for a woman's right to choose, for LGBTQ rights and then ask the people of Massachusetts to support Geoff Diehl and then waffle on whether or not he's going to support Geoff Diehl," the Democratic challenger said. "Where does he stand? For me, these are not issues that I base my decisions on and my positions on based on political calculations."

The two clashed Wednesday on issues other than Geoff Diehl, including transportation, scandals at the Massachusetts State Police, and single-payer health care. And as in their first contest, Gonzalez and Baker on Wednesday sparred over which candidate has a vision to lead Massachusetts. Gonzalez knocked Baker for delivering "status quo stuff," while Baker accused Gonzalez of offering voters empty and expensive promises.

On transportation, the candidates rehashed issues of investment in public transportation and whether Baker's efforts over his four years in office have been sufficient. Gonzalez touted his $3 billion revenue plan, which relies on a tax on university endowments and a tax proposal similar to the millionaire's tax proposal the Supreme Judicial Court kept off the November ballot, as the key to a better transportation network.

"We have to be honest with voters that we need to invest in our transportation system to get it to where it needs to be," Gonzalez said. He added, "I am saying there is going to be a clear choice. I am going to ask the wealthy to pay more in taxes so we can make these investments that will make a difference to working families across the state."

Braude pressed Gonzalez on whether his revenue plan is realistic, given that part of it could require the Legislature to adopt a constitutional amendment and another part is not widely popular with lawmakers.

"It's a very specific plan to raise $3 billion each year by the end of my first term, which is $3 billion more than zero, which is his plan," he said.

At another point in the debate, Baker fired back at Gonzalez's contention that his $3 billion revenue plan will cover the costs of everything he has proposed on the campaign trail.

"The notion that he has put enough plans on the table to fund all the stuff he's promising and committing to simply isn't true," Baker said. "That's not really governing or leadership, that's politics and in addition to that we have a plan."

Gonzalez and Baker tangled over the drip-drip-drip of scandal at the Massachusetts State Police, including recent reports that the agency moved to destroy reams of records after its overtime and payroll practices fell under scrutiny earlier this year. Baker called the attempt "a mistake" while Gonzalez categorized it as "an attempted coverup."

"People who are indicted, people who pled guilty, criminal activity during the governor's tenure," Gonzalez said. He asked Baker, "When are you going to take charge? And you haven't fired a single person at the State Police. When are you going to fire someone?"

Baker put up a defense of State Police Colonel Kerry Gilpin, whom Baker tapped to lead the agency amid a different scandal at the State Police last year, saying that she was the one who collected data on the 46 troopers accused of violating overtime and personnel practices, and turned the data over to the U.S. attorney and attorney general.

"She's the one, with her team, who followed this string, developed the cases and submitted them to the appropriate authorities for prosecution," Baker said. "And she's the one who blew up Troop E, which is where the vast majority of the problems were."

The two former health insurance executives also disagreed Wednesday on single-payer health care, with Gonzalez labeling himself "a former health insurance CEO who thinks we need to get rid of health insurance companies."

While Baker claimed Gonzalez's single-payer plan would cost $30 billion, Gonzalez said his plan would actually end up reducing overall health care spending, which topped $61 billion last year in Massachusetts.

"Health care costs are crushing families and government and businesses," he said. "The system is way too complicated. We need to simplify it and we need to save money and going to a single-payer system will save us money."

Baker said single-payer is unrealistic and pointed to Vermont as an example of a state where a single-payer health system was determined to be too costly and burdensome to actually implement. He said Gonzalez "has zero evidence about everything he just said with respect to single-payer."

Wednesday's debate aired live on 89.7 FM, WGBH television, WGBY public television in Western Massachusetts, C-SPAN, and was streamed on wgbhnews.org and on WGBH's app. Unlike the first gubernatorial debate, Wednesday's joust was not airing in direct competition with a Red Sox playoff game.

With less than three weeks to go until Election Day, many voters across Massachusetts are just tuning into the race for governor. Polls have shown Gonzalez is not well known among voters, even Democrats, while Baker frequently ranks among the most popular governors in the country and has widespread name recognition in Massachusetts.

A WBUR/MassINC poll released in late September found that 45 percent of voters have never heard of Gonzalez and 37 percent of the Democrats polled claimed they hadn't heard of their party's nominee either. Overall, the poll said that Baker held a 66 percent to 22 percent edge in his race against Gonzalez.

The Democrat is also getting badly outraised by the incumbent. Gonzalez has raised $937,688 for his campaign and had $201,610 on hand in his account at the end of September. The Democratic ticket has qualified for $542,284 in pubic financing and could receive up to $173,258 in additional public matching funds based on fundraising.

Baker had $4.47 million on hand as of Monday and his running mate Karyn Polito had another $2.84 million in her campaign account. The Republican Governors Association has also pumped $6.625 million into Massachusetts to support Baker through the Commonwealth Future PAC.

The Republican incumbent Baker is running for governor for a third time, seeking a second four-year term in office. Democrat Gonzalez is running for statewide office for the first time and is hoping voters will agree with him that he could do better than Baker.

Both candidates will meet for a third and final debate just days before voters go to the polls. The two will square off at 7 p.m. on Nov. 1 in a debate hosted by a consortium of Bay State media outlets. Election Day is Tuesday, Nov. 6.