Halfway through a forum this week featuring Republican gubernatorial candidates Charlie Baker and Mark Fisher, I began to wonder why GOP officials fought so hard at their state convention to keep Fisher off the ballot.

Fisher is a plus, not a negative, for the Baker campaign. Compared to the Democrats running for governor, Baker still seems fairly conservative. He is pro-choice and in favor of gay marriage, yet he’s a hardliner on taxes and spending. (Remember that Joseph Avellone, who favors a carbon tax, calls himself the moderate in the Democratic primary race.) But next to Fisher, Baker comes across as a moderate.

Fisher is articulate and engaging, but he has no name recognition, relatively little money, and his embrace of tea party principles makes it easier for Baker to position himself as the moderate Republican he needs to be to attract enough independent and Democratic voters to win the governor’s office in Massachusetts.

Baker’s campaign this year seems designed to reinforce a moderate image. During his first run for governor in 2010, Baker often seemed to be uncomfortable. He was intense and many felt he came across as angry at times, particularly on tax matters. He tended to see issues in black and white terms. Friends say they didn’t recognize the candidate who ran in 2010.

This time around Baker is toning down the anger and adopting more nuanced positions on a wide variety of issues. In 2010, for example, he came out forcefully against Cape Wind, calling it a “sweetheart deal” for the project’s investors and a negative for the business climate. But now he says Cape Wind is a done deal and it’s time to move on.

In 2010, he opposed South Coast Rail, a proposed commuter rail line between Boston and Fall River and New Bedford. Now he answers questions about South Coast Rail ambiguously. He says the rail project is worth exploring, but adds that he would prefer South Coast cities to develop their own job base rather than relying on jobs in Boston.

As Boston Globe columnist Tom Keane has pointed out, Baker has even co-opted the Democratic issue of income inequality.  He has taken a liberal rallying cry and transformed it into a guiding economic principle for a Republican who doesn’t want to see residents of Massachusetts who live outside Boston get left behind.

At this week’s forum, where I was a member of the panel, Fisher and Baker had a very cordial discussion. They agreed on a number of issues. They opposed inflation indexing for the gas tax and expansion of the bottle deposit law. They both questioned casinos as an economic development tool and said it was worth exploring whether Boston could host the Olympics. Fisher, the owner of an Auburn metal manufacturing company, signed a pledge not to raise taxes; Baker says he has no intention of raising taxes but won’t sign a pledge because he says that might prevent him from revamping the tax code.

Where the two candidates were in disagreement, the difference was striking. In 2010, Baker hemmed and hawed on whether climate change was occurring and whether humans were causing it. This time around Baker is very clear on the issue. “The climate is obviously changing and there’s data out there to support that,” he said.

By contrast, Fisher said climate change is a myth. “The science is not there,” he said. “It’s become politicized.”

Is health care a human right?

“I don’t believe so. I think it’s a nice thing,” said Fisher. “Where do we stop with this? Do we have a right to a home, a car, an in-yard pool? We have the right to pursue happiness… I’m not for government-imposed happiness.”

Baker says health care is a right. “It’s already a basic right under federal law and it’s a basic right under state law,” he said. “No one knows when they’re going to fall off a ladder, break their leg, or discover they have cancer.”

Perspective is important in politics. Alone, Charlie Baker is the Republican in the race for governor. With Mark Fisher in the GOP primary, Baker is the moderate Republican in the race for governor.

Bruce Mohl oversees the production of content and edits reports, along with carrying out his own reporting with a particular focus on transportation, energy, and climate issues. He previously worked...