Pete Buttigieg has recently enjoyed a surge in swing-state polls.

That’s one reason he was the subject of some debate-night swipes from his rivals on Thursday.

Based on Insider polling, candidates like Sen. Elizabeth Warren and Sen. Bernie Sanders have an advantage over Buttigieg because his supporters like them but theirs don’t reciprocate.

For Sen. Amy Klobuchar, the mayor’s success presents a problem.

About three-quarters of people who have told Insider they’d be happy with Klobuchar as nominee say the same about Buttigieg.

That’s a recipe for a rough night for the mayor of South Bend, Indiana.

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Thursday night’s Democratic presidential debate contained some of the most compelling fireworks of the campaign so far, with Mayor Pete Buttigieg of South Bend, Indiana, being the target of swipes by rivals, particularly Sen. Elizabeth Warren of Massachusetts and Sen. Amy Klobuchar of Minnesota.

The reason for this is simple: He’s up in the polls, but really quite vulnerable. His supporters tend to really like the frontrunners, and he hasn’t been able to nail down support to his campaign quite as well as some of his rivals have.

Insider has been conducting a recurring SurveyMonkey Audience national poll for almost a year, specifically asking those who say they’re registered to vote and will probably participate in the Democratic primary who they’d be satisfied with as nominee.

You can download every poll here, down to the individual respondent data, and see the sample size and margin of error for all four of the polls we cite here. (Read more about how the Insider 2020 Democratic primary tracker works.)

This lets us supplement top-line data with information about whose constituencies overlap and whether a given candidate’s supporters tend to favor a rival. Given that we’re still in the period when candidates are trying to command a lane, that’s important.

Foto: Candidates onstage before Thursday night’s debate in Los Angeles.sourceASSOCIATED PRESS

Why Mayor Pete has a target on his back

The thing Pete Buttigieg has going for him is that lots of people like him.

The thing Pete Buttigieg has working against him is that the people who like him also like a lot of other candidates too.

Looking at the seven polls Insider has conducted since mid-October, 816 respondents out of 1,625 possible Democratic primary voters said they’d be satisfied if Buttigieg were the nominee. That’s the fourth-best in the set. But here’s the catch:

76% of those people were also satisfied with Sen. Elizabeth Warren, which is 13.3 percentage points higher than she even does among Democrats as a whole.

63% were also satisfied with former Vice President Joe Biden, 9.1 percentage points better than his overall performance.

Even 53% were satisfied with Sen. Bernie Sanders of Vermont as nominee, roughly even with his overall performance. Keep in mind, Sanders and Buttigieg have significant policy differences, and still Sanders is holding his own among Buttigieg fans.

It doesn’t stop there. Compared with the typical Democratic primary voter, those satisfied with Buttigieg have been even more likely to be happy with Sen. Cory Booker of New Jersey (13 percentage points higher than normal), Klobuchar (6 percentage points higher than normal) and the former US Housing and Urban Development Secretary Julián Castro (3 percentage points higher).

Foto: Buttigieg and Warren.sourceChris Carlson/AP Images

The issue for Pete is that the affection isn’t mutual

It would be one thing if Buttigieg were also doing exceptionally well among those rivals‘ supporters. It is not, it turns out, that one thing. Quite the contrary:

Just 42% of those satisfied with Warren have said they would be content with Buttigieg as nominee, 8 percentage points lower than his overall performance.

38% of those satisfied with Biden are all right with Buttigieg, 12 percentage points less than normal.

A paltry 32% of Sanders fans say they would also be happy with Buttigieg, fully 19 percentage points lower than his typical performance.

At the same time, a candidate like Klobuchar can’t be blamed for looking at her own numbers – 74% of her supporters also say they are satisfied with Buttigieg as nominee, 24 percentage points higher than typical – and seeing that jumping in on this particular dog pile (and emphasizing her own considerable political and legislative experience in the process) is just plain good politics, drawing a distinct contrast for supporters whose eyes may be straying toward South Bend.

This puts Buttigieg in an unenviable position during debates like these. His approval numbers are comparatively strong, but his supporters are more than fine with any of the other frontrunners. Those frontrunners have little to lose getting in the mix with Buttigieg, given that their own bases of support don’t particularly care for Buttigieg to begin with.

And for a candidate like Klobuchar – someone who is stuck sharing a lane with Buttigieg – this will be one of the final times to really make a play for those waffling between Minneapolis and South Bend.

It was only a matter of time before someone mentioned the wine cave.