David Zalubowski / AP

NASHUA, N.H.—Some people respond to being told that they have cancer with tears, or by scaling back plans. Michael Bennet responded to his prostate-cancer diagnosis, announced last week, by planning trips here to New Hampshire and to Iowa on Monday, redoubling his interest in a presidential campaign few observers right now say they see any path for.

The Colorado senator told me that his own health helped persuade him to run, and to lean in on talking about health care. While he hasn’t filed any paperwork yet, Bennet said on Saturday that he is running, unless his treatment produces some sort of bad surprise.

“It’d be a great excuse not to run if I didn’t want to run—this would be the best excuse you could ever have, and from that point of view, it’s been very clarifying, because I haven’t had that feeling at all,” Bennet told me, speaking after an hour-long session with about 30 people at a coffee shop in the center of this small city late Saturday afternoon. “It only underscores how infuriating it is that we have a guy in the White House who’s made a mockery of dealing with the problems in our health-care system.”

Bennet will have surgery at the beginning of the upcoming Senate recess, and he said he’s not thinking much about the diagnosis, thankful to have insurance and optimistic that everything will proceed according to plan. Bennet, Denver’s former superintendent of schools, was appointed to the Senate in 2009 and has twice won the seat, in 2010 and 2016. His brother, James, is a former editor in chief of The Atlantic and the current editorial-page editor of The New York Times. That his cancer was caught despite a lack of symptoms, he said, emphasized to him the importance of screening and preventative medicine.

Bennet said that his conversation with voters at the coffee shop reinforced why he reintroduced his Medicare-X bill, which provides a Medicare option. But unlike Bernie Sanders’s Medicare for All bill, which has become popular in the Democratic primary field, his plan would not eliminate all private insurance.

That, Bennet said, would be the wrong way to go. But whatever internal disagreements Democrats might have over a plan, he added, at least the debate makes clear that his party is for helping people with health care, and the Republicans are not. The GOP solution, he said, is “just a bunch of gibberish.”

He’s clearly been paying attention to the dynamics of the primary race, though. At one point in the coffee shop, Bennet jumped up on a bench and waved his hands for a few seconds, imitating the stand-on-things-and-gesticulate stumping style of Beto O’Rourke that has become an internet meme and a running joke among several Democratic candidates.

As for how the cancer is affecting his presidential run, Bennet acknowledged that it’s slowed him down, and might get in the way of his making the stage for the first Democratic debates at the end of June, for which candidates need to meet a minimum threshold of 1 percent in polling or 65,000 donors.

“We won’t have to stop. We’re going to continue to talk to staff,” Bennet said. “At some point it could have an effect on whether we get to the debate stage or not, but I think we have a good chance to get there.”

At the direction of the White House chief of staff, the Justice Department has now signed on to a lawsuit filed by Republican states to repeal Obamacare in its entirety. Donald Trump himself as recently as 11 days ago was promising a new health-care plan, saying that the GOP would soon be known as the party of great health care, though he pulled back from that after opposition from Senate Majority Leader Mitch McConnell. Now he says he’s delaying releasing a new health-care plan until after the 2020 election, even as his chief of staff held meetings over the weekend to continue exploring how to move forward and try to come up with the replacement to Obamacare that Republicans have been promising for almost a decade.

Bennet said he’s eager to take on the principle of fighting partisan gridlock and restoring functional government, which is at the heart of the campaign he wants to run. And now he’s got a more personal stake in the health-care debate. “When you have something like this, it seems even more outrageous,” Bennet told me, referring to Trump’s recent gyrations on health care. “But it’s not like I have to look very far to find people in my state whose lives are being turned upside down because of the unpredictable nature of Donald Trump’s lack of health-care policy.”

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