WATERTOWN, Minn. - Two years ago, Scott Jensen had built a reputation as a moderate Republican state senator from Chaska, whose experiences as a physician prompted him to cut deals with Democrats to lower prescription drug prices and try to find a pathway to new gun control measures.

Now he's a GOP frontrunner in the race for governor on a platform of questioning the effectiveness of vaccines, social distancing and mask mandates in battling COVID-19. At a recent GOP governor candidate debate in Wayzata, Jensen endorsed "stand your ground" legislation, saying he'd shoot "dead" any would-be robber or carjacker who threatened him.

"I'm not easily constrained. I don't fit neatly in any boxes," said Jensen, 67, defending his unconventional political trajectory in an interview from the family clinic he runs in this small exurban city. "I'm just not impressed with the same old thing."

His approach has helped him gain traction with conservatives in a field of more than a half dozen GOP candidates angling to challenge Gov. Tim Walz next fall. But it's triggered fierce backlash from critics who say his views on the pandemic are dangerous. Former allies are befuddled by what they see as a 180-degree shift in just a few years, mirroring the broader transformation of the Republican Party under Donald Trump.

"He's a physician yet he's crossed so many lines during this whole pandemic. It's worrisome," said Nicole Smith-Holt, who worked with Jensen in the Legislature to pass an insulin affordability bill after her son died from lack of access to the lifesaving drug. "Watching him now when he's doing town halls or on his social media feeds, this is not the person I knew."

While less bombastic and quieter in style than the former president, Jensen's messaging around COVID-19 has drawn support from the Trump faithful. His success in the nomination process will be a test of whether Minnesota Republicans plan to chart a new path or embrace Trump-era politics as part of their electoral strategy in the 2022 midterm election.

"Scott Jensen is definitely appealing to those voters who have developed a distrust of institutions," said David Sturrock, a former state Republican Party official and a political science professor at Southwest Minnesota State University. "Donald Trump ran that way, though with a very different tone and style."

In the race for governor, Jensen is leaning heavily on his medical credentials and positioning himself as the outsider in the field. He's Dr. Scott Jensen on campaign materials, and he's often seen wearing a white lab coat or sitting in his clinic in frequent videos posted to social media.

"I describe it as his bedside manner. His format for the videos is very successful for him," said Amy Koch, a political strategist and former GOP Senate majority leader. "He doesn't rely on the media, much just like President Trump didn't and many other candidates don't now."

But unlike many past candidates who fashion themselves as outsiders, Jensen grew up immersed in state politics. His father, Carl Jensen, spent more than two decades on and off in the state House and Senate between 1951 and 1980. Before running for an open seat in the state Senate in 2016, Jensen served on the Waconia school board.

During the four-year term he served at the Capitol, Jensen became known as an eccentric and unpredictable legislator. He was willing to put his name on a bill to legalize recreational marijuana so that the bill could get a hearing. He backed a bill to let local governments implement ranked-choice voting, which other members of his caucus have tried to ban.

His experiences as a family doctor put him at the center of legislation to regulate pharmacy benefit managers and negotiations. Jensen was open to supporting universal background checks, drawing backlash from gun groups at the Capitol. Now, Jensen says he wants to have conversations about background check systems but he doesn't support those changes.

"The human mind is a dynamic instrument; we take in new data, we have new experiences and all of those things shape us," Jensen says of his views. "I think my perspectives change; I don't think my core convictions have."

As COVID-19 took hold last year, Jensen's focus pivoted to the pandemic. He appeared on Fox News suggesting health officials were coaching doctors to fill in COVID-19 death certificates, even without confirmation, putting him on the national stage as a skeptic to the pandemic's response. He said his concerns also prompted his run for governor.

Since then, Jensen briefly joined a lawsuit seeking to halt youth vaccinations that was filed by a woman under indictment for participating in the Jan. 6 U.S. Capitol riot. He also called for "civil disobedience" in the face of federal vaccine mandates.

"Scott Jensen has ignored science and fact and probably done more harm in this state around COVID than anyone I know in terms of being a public servant," said Ken Martin, the Minnesota DFL Party chair.

Sen. Matt Klein, DFL-Mendota Heights, bonded with Jensen as the only other doctor serving in the Senate, but he's struggling to understand where Jensen's positions are coming from on COVID-19.

In 2017, they both ran to DFL Gov. Mark Dayton's side when the governor collapsed on the House floor during his State of the State address. But Klein was surprised to see Jensen quickly turn to the television cameras after Dayton left the chamber.

"To me it was a harbinger of things to come, that he was willing to exploit that moment," Klein said.

Jensen said the critiques of his positions on vaccinations and the pandemic have been misrepresented. He's concerned about vaccinating children, but he said the science does point to benefits of vaccinating people over 75. He's not vaccinated against COVID-19 because he said he has immunity after contracting the virus. The CDC recommends vaccination even if you've had COVID-19.

"I've always been respectful of vaccines, but also skeptical," he said. "It's hard to be nuanced with the world and social media."

The virus isn't the only issue that's important to him, he said. Jensen wants Republicans to talk about conservation and clean water to attract young people to the party. He rejects some comparisons to Trump, while acknowledging they both have a "distaste for politics as usual."

And like Trump, Jensen doesn't spend much time dwelling on whether positions he's taken in the past will stick to him in the upcoming race for governor.

"I think there's a tendency in politics and the public sector to stick to your guns even if you're wrong," Jensen said. "I'd create a culture where it's OK to say, that's on me, that's the way humans are wired. We're sure not going to sit there saying we're right all of the time."