BILL WELD ISN’T going to be president. He isn’t going to be the Republican nominee for president. In the one-in-a-hundred, best case scenario, he will win New Hampshire and then end up with no constituency when the race moves to conservative, evangelical-dominated electorates. Despite his practically nonexistent chances of victory, Weld can make a major impact on the 2020 presidential race and deal real political damage to the president he loathes.

Bill Weld is no stranger to hopeless crusades. Though he’s best remembered for his two victorious gubernatorial campaigns, Weld’s first race was in 1978, when he lost the attorney general’s race by over 50 points to beloved Democratic incumbent Frank Bellotti. Compared to that political suicide mission, challenging Donald Trump in the Republican primary looks easy.

There is simply no significant constituency for Weld among Republican primary voters. In the 1990s, he was considered a liberal Republican, even running to the left of Democrat John Silber in his first gubernatorial campaign on some issues. By contemporary standards, Weld makes Susan Collins look like Steve King.

Weld alongside Frank Bellotti, who trounced him in the 1978 race for attorney general, at an event in Boston in 2015. (Photo by Michael Jonas)

He’s proudly pro-choice, pro-trade, and pro-immigration. Not only does he oppose building the border wall, he supports amnesty for illegal immigrants currently in the country. While the vast majority of Republicans think the Mueller probe is a witch hunt, Weld told Reason magazine that Trump has committed worse crimes than Richard Nixon. In 2008, Weld endorsed Barack Obama and then urged voters to support Hillary Clinton in the closing days of the 2016 race even while running as the Libertarian candidate for vice president.

In a party increasingly reliant on non-college-educated white voters, Weld is an anachronism. A proud patrician (the 19th member of his family to attend Harvard) who can pontificate about classical philosophy, he is a throwback to that peculiar type of New England Republicanism synonymous with WASPs, repp ties, and Brandy Alexanders. They didn’t share a governing philosophy but an attitude, one that combined noblesse oblige with a desire for honest government and balanced budgets. Once common, famous blue-blooded dynasties like the Lodges, Scrantons, Keans, and Bushes have gone the way of undarted suits and the haberdashers that sold them.

Weld no doubt sees himself as the spiritual successor to Andrew Peters, the proud Boston Brahmin whose 1917 mayoral campaign stopped, albeit temporarily, the roguish James Michael Curley. Instead, Weld’s quixotic bid is more like Curley’s 1949 mayoral race, when the legendary mayor lost his bid for reelection. Curley was 75, only two years older than Weld is now, and the ethnic conflict he built his political career on was dying. The race was fictionalized in Edwin O’Connor’s The Last Hurrah, and its sequel could be set in New Hampshire, where the last of the St. Grottlesex set tries to win over a party that he can barely recognize.

Despite its longer-than-long odds, Weld’s campaign can still prove immensely consequential in the 2020 presidential campaign. The question isn’t whether he wins in New Hampshire, but whether he loses like Eugene McCarthy or Pete McCloskey. McCloskey’s 1972 anti-war primary challenge against President Nixon went nowhere, winning 11 percent of the vote in New Hampshire and one delegate at the Republican National Convention. Today it’s best remembered for a bizarre episode that involved then-19 year-old Roger Stone donating to McCloskey while posing as a member of the Young Socialist Alliance. Nixon’s campaign leaked the donation to the Manchester Union Leader as proof that McCloskey, like all anti-war radicals, was a Soviet fellow traveler.

McCarthy, on the other hand, changed the course of history in 1968 when he lost the New Hampshire primary to Lyndon Johnson. The eccentric professor-turned-politician came within 8 points of the sitting president, despite pre-election polls showing McCarthy mired in the low teens. The next morning, Robert Kennedy, who had ruled out a presidential bid, announced he was reconsidering. Kennedy was a far more credible candidate than the mercurial, uncharismatic McCarthy. His entrance into the race drove President Johnson to drop out, and had he not been assassinated in June of that year, Kennedy would likely have been the 37th president.

Weld – if he sticks around at least through next year’s New Hampshire primary — is on track to become a footnote of presidential political history, just like McCloskey. His campaign lacks a clear animating issue, he hasn’t held elected office in over two decades, and lacks the political and fundraising infrastructure for a serious campaign.

Or, Weld could surprise like McCarthy did. Far stranger things have happened in American politics. In our current political climate, stranger things happen every month. While Trump seems to have an iron grip on Republican voters, with 89 percent approval from his party, favorable poll numbers can fade quickly. If there’s even a mild economic slowdown, an obvious foreign policy screw-up, or an ongoing domestic failure like the Bush administration’s response to Hurricane Katrina, Trump’s poll numbers could plummet (as they started to during last month’s shutdown).

If Weld runs a strong grassroots campaign and Trump’s overall approval numbers fall by August, Weld could end up polling in the mid-30s among New Hampshire voters. If even liberal, out-of-touch Bill Weld seems like he might upset the sitting president, a lot of establishment Republicans could rethink their plans.

The bench of credible Trump primary opponents is tiny — only Nikki Haley and Ben Sasse come to mind — but if the President appears vulnerable, a credible opponent would have a lot of resources. The large swath of Republican politicians, consultants, and donors who loathe Trump but think he has an unshakable grip on the party would flock to an opponent with a meaningful chance of victory.

In this scenario, Trump would likely still win the nomination. The advantages of incumbency are almost impossible for an intraparty challenger to overcome. However, a bloody nomination fight would all but guarantee a Democratic victory in 2020. No modern president has won reelection after a serious primary challenge.

Having a primary opponent takes away one of the biggest advantages of an incumbent president, who gets to campaign and raise money unchallenged while the other party’s would-be nominees fight. Even more damaging, the Democratic nominee will echo the primary opponent’s arguments, which gain credibility when they are advanced by a member of the president’s own party. A credible primary opponent won’t guarantee Trump’s defeat, but it will make it far more likely.

William F. Weld has enjoyed his 73 years on Earth. He’s been a prosecutor, a politician, a venture capitalist, and even an author. He jumped in the Charles River, wore sunglasses to his inauguration to shield his hungover eyes from the sun’s cruel glare, and wrote a surprisingly moving coming-of-age novel. His hatred for Trump is so strong it’s practically palatable. Why wouldn’t he want to have one last political adventure? A presidential campaign gives Weld a chance, albeit a small one, to make history and have a lot of fun along the way.

Brian Jencunas is a Massachusetts-based Republican speechwriter and political strategist who has consulted for many successful local, municipal, and statewide political candidates, as well as ballot initiatives and independent expenditure groups.