Mary Altaffer / AP

Imagine you’re Pete Buttigieg. You had the best October of any candidate in the Democratic presidential race. On September 15, you trailed Joe Biden in Iowa by more than 20 points and both Elizabeth Warren and Bernie Sanders by at least 10. Kamala Harris was beating you, too. Now, by some measures, you’re in second place, a few points below Warren. You’re effectively pounding her on health care, because most Democrats prefer your comparatively modest reforms to her more radical ones. And you’re finding creative ways to imply that she’s unelectable—an attack that’s been buttressed in recent days by alarming high-profile polls about her weakness against Trump in battleground states.

Things are looking up. Until Michael Bloomberg comes along.

The New York Times reported yesterday that Bloomberg was “actively preparing to enter the Democratic presidential primary.” Sources in his camp tell reporters he’s alarmed about Warren, whose rise has elicited near-panic on Wall Street and whose ability to beat Trump in a general election Bloomberg is said to doubt. But Warren is no longer rising. As Nathaniel Rakich of FiveThirtyEight recently noted, her “polls have leveled off” in the early-primary states. In national surveys, her numbers have dipped.

A Bloomberg candidacy could give Warren her mojo back. What could be better for the Massachusetts senator, who has built her candidacy on the claim that plutocrats control America’s government, than to run against a billionaire 51 times over who keeps slamming her proposed wealth tax, which more than 80 percent of Democrats support. By last night, Warren’s campaign was already fundraising off a possible Bloomberg candidacy. Ironically, the former New York mayor is empowering the very forces that he means to thwart.

If Bloomberg stops anyone, it will most likely be the candidate who actually is rising: Buttigieg. Bloomberg was reportedly animated by Joe Biden’s palpable deficiencies as a candidate. But the South Bend, Indiana, mayor has already capitalized on them. He’s overtaken Biden in Iowa and out-raised him nationwide. He’s moved aggressively into Biden’s centrist lane while drawing more grassroots support than other relative moderates, such as Senators Harris, Cory Booker, Amy Klobuchar, and Michael Bennet. Were Bloomberg primarily interested in ensuring that neither Warren nor Bernie Sanders turned America into another “Venezuela,” he could have done what many other center-left Democratic establishment types have done: given Buttigieg the cash to compete with Warren’s and Sanders’s small-donor-powered campaigns.

Instead, Bloomberg is considering spending vast sums of money to muscle onto Buttigieg’s moderate turf, thus impeding his rise, even though the South Bend mayor is, by most relevant criteria, a much better candidate. Buttigieg is 37, which offers a useful contrast to the four septuagenarians (Warren, Sanders, Biden, Trump) he’s competing against. Bloomberg is 77. Buttigieg served in Afghanistan; Bloomberg didn’t serve in Vietnam. Buttigieg lives in the Midwest; Bloomberg lives on the Upper East Side of Manhattan (and, at least as of 2015, in Bermuda, London, Westchester, the Hamptons, Florida, and Vail, Colorado, as well). Buttigieg has never tried to ban Big Gulp sodas. And most important, a substantial number of Democrats are actually enthusiastic about Buttigieg’s candidacy. By contrast, an October Fox News poll found that only 6 percent of likely Democratic primary voters would definitely vote for Bloomberg if he got into the race, while 32 percent definitely would not. In January, NPR asked Democrats and Democratic-leaning independents how they felt about 10 declared or potential Democratic presidential candidates. Bloomberg was the only one without a positive net approval rating.

Maybe Bloomberg has been seduced by his past political success. Unlike fellow billionaire Tom Steyer, he has won elections before. As a political novice in 2001, Bloomberg bought his way into the New York mayoral race and, after winning, proved popular enough to be reelected twice. Perhaps he thinks he can engineer a similar scenario in a presidential campaign. But Bill de Blasio got elected mayor of New York, too, and Bloomberg’s presidential bid would prove as superfluous as his successor’s. De Blasio, the left populist, entered a Democratic race that already included two, Sanders and Warren, with demonstrably broader appeal. Bloomberg would enter a race that already includes a compelling center-left pragmatist, Buttigieg. The difference is that Bloomberg can spend hundreds of millions of dollars and kill the momentum Buttigieg desperately needs to maintain.

The Warren camp appears gleeful. Buttigieg’s campaign is sullenly silent. Within hours of the news that Bloomberg might run, Warren had welcomed him, via tweet, to the race. On his Twitter feed, Buttigieg had said nothing at all.

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