JB Pritzker is losing weight. Even Donald Trump is taking notice.

CHICAGO — Gov. JB Pritzker doesn’t quite look the same on the campaign trail these days. His pants hang loose, his jacket buttons no longer strain — the Democrat known for his barrel-shaped frame cutting a noticeably trimmer silhouette in his bid for a third term.

“How about, just for health,” Pritzker said when POLITICO asked about his weight loss.

Or, as just about anyone familiar with the rich history of pre-presidential pound-shedding is starting to suspect, how about for 2028.

“Looks like he's getting ready for a fight,” said Mark McKinnon, a former media adviser to George W. Bush and John McCain.

The fight over Pritzker’s appearance picked up this week, when President Donald Trump told reporters that the governor “should spend more time in the gym.” Pritzker, whose leaner profile has turned heads everywhere from Springfield to image-obsessed Los Angeles, responded that “it takes one to know one on the weight question,” calling Trump a “bully,” and saying, “the president, of course, himself is not in good shape.”

But even Trump has noticed that Pritzker, who has been spotted recently in running shoes, is down a few pounds — and earlier this month suggested what that might mean politically. “I understand [Pritzker] wants to be president. I noticed he lost a little weight, so maybe he has a chance,” Trump said.

Pritzker, a potential 2028 presidential contender, would hardly be the first candidate to drop weight ahead of a campaign.

Before the 2012 presidential campaign, former Mississippi Gov. Haley Barbour said, “If you see me losing 40 pounds, that means I’m either running or have cancer.”

New Jersey Gov. Chris Christie’s slimming down in 2014 was seen as evidence he was preparing to seek higher office. And Mike Pompeo, the former secretary of state and CIA director under Trump, drew headlines for dropping a staggering 90 pounds before deciding not to run in 2024.

In modern American politics, weight loss comes with the territory. Candidates are “thinking about image and about health,” said Republican consultant David Kochel. “But they’re always thinking about the next move.”

He pointed to former Arkansas Gov. Mike Huckabee “losing a bunch of weight,” and Jeb Bush taking up a paleo diet before his run for president in 2016.

Now, said Kochel, “You’ve got these GLP-1s that people can take. If you want to look younger and healthier, it makes total sense. You can probably come up with a dozen examples.”

That Trump, not known for being svelte, would poke at Pritzker, might say more about campaign style, he added.

“There’s some tough politics in Chicago and in my home state of Iowa, but they tend to be masked a little bit with the ‘Iowa nice,’ ‘Illinois nice’ and ‘Minnesota nice’ — always being a little more gentle with language,” said Kochel. “Trump doesn't come out of that tradition. He’s a tough, street-fighting politician. That's his brand, and it's worked for him. So maybe there’s a point to JB trying to get into some fighting shape.”

In Illinois, observers of Pritzker’s weight loss are just as likely to point to his family history as politics. Pritzker’s father, Don Pritzker, the Hyatt Hotels president, was just 39 when he died of a heart attack in 1972. His youngest son was 7 at the time, and would grow into the same round face and stocky build as his father.

“We like to analyze every little detail of every national politician,” said Kelly Dietrich, founder of the National Democratic Training Committee. “Americans can over-think every move a candidate makes. They might go out to eat tonight, and the question is ‘Does that mean he doesn’t support gig workers?’”

Regarding Pritzker, “It’s a personal health decision,” Dietrich said. “The man is an accomplished governor with an impressive track record, and one of the front-runners for the presidential race. I don't know that we should read too much into the tea leaves here.”

Bob Shrum, the veteran Democratic consultant who now heads the Center for the Political Future at the University of Southern California, doesn’t think a candidate’s appearance carries the weight it once did in American politics. With Trump, he said, the country “has gotten used to seeing somebody who has orange hair, a tie that hangs too long” and “isn’t exactly the picture of robust health.”

“I don’t think voters are going to accept or reject somebody on the basis of their weight. I just don’t think that’s it. The weight of their ideas will count a lot more — the weight of their message, whether they’re able to connect with people — that’s what matters,” he said.

But it’s not just physical appearance candidates have to worry about when it comes to their weight. The rigors of a looming campaign can motivate them to shape up, too.

“It’s a long march going to Iowa, New Hampshire, South Carolina, Nevada — little towns sitting in cars, planes, trains. It's grueling,” said a Democratic consultant who’s worked on presidential campaigns and was granted anonymity to speak freely. “So being in the best possible physical shape is an asset. If someone is getting in better physical shape, it may not just be about appearance. It’s about prepping for the ultimate political marathon.”

Pritzker has long taken his weight in stride. Even while losing pounds and inches, the governor played along with the fat jokes in a recent appearance on “Jimmy Kimmel Live.”

In a skit, Kimmell asked Pritzker to read off some nicknames he could pick for himself before Trump does it for him.

Pritzker smiled as he read them aloud, including “JB Pizza,” “JB Back Ribs,” “J. Biggie” and “JB ‘The Refrigerator’ Pritzker.” And the governor offered a couple of his own, including “J. Beefy.”

Even the campaign theme of Pritzker’s first two gubernatorial races embraced his stature. The message to Illinois voters: “Think Big.”

The message has changed for his third gubernatorial campaign: It’s “Keep Illinois Moving Forward.”

Everyone’s noticing. At an event in Los Angeles earlier this month, many attendees in the heavily Democratic audience said they’d come partly out of curiosity about whether the Midwestern governor could be their party’s next standardbearer. In a city famous for surface judgments, some said Pritzker’s trimmer look stood out.

“Yes, because the last really heavyweight president was William Taft,” one gray-haired attendee said, adding, “Excepting Donald Trump.”