
AP Photo/John Locher
From left, Democratic presidential candidates Sen. Amy Klobuchar, D-Minn., former Vice President Joe Biden, South Bend, Ind., Mayor Pete Buttigieg, Sen. Elizabeth Warren, D-Mass., businessman Andrew Yang and Sen. Cory Booker, D-N.J., stand onstage during a fundraiser for the Nevada Democratic Party, Sunday, Nov. 17, 2019, in Las Vegas. (AP Photo/John Locher)
Amy Klobuchar has ended her campaign, making her the third candidate in as many days to exit the 2020 Democratic primary after billionaire Tom Steyer and former South Bend Mayor Pete Buttigieg dropped following their disappointing results in the South Carolina primary.
Buttigieg and Steyer ended their campaigns ahead of Super Tuesday, the enormously consequential primary when approximately 35% of the entire national primary's delegates are awarded over the course of a single day. But they - at first - neglected to endorse, effectively allowing their backers to navigate the remainder of the primary without guidance from their preferred candidate.
Klobuchar, however, decided to endorse former Vice President Joe Biden immediately after dropping out, and shortly after that announcement it was reported that Buttigieg too would be endorsing Biden.
For the past several months, Insider has been conducting a recurring SurveyMonkey Audience poll to track the state of the 2020 Democratic primary field. You can download every poll here, down to the individual respondent data. (Read more about how the Insider Democratic primary tracker works here).
We've been asking respondents to select from the list of contenders who they would be satisfied with as nominee, allowing them to select as many as possible. This lets us figure out what the overlapping coalitions of the Democratic electorate look like, to see who's competing for the same delegates.
First, Klobuchar.
Had she left the race and declined to endorse, those who support her would probably be deciding between Sen. Elizabeth Warren and Vice President Joe Biden. Here's the numbers from pre-South Carolina, including Buttigieg.

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About half of Klobuchar's supporters like Mike Bloomberg and a little more like Sen. Bernie Sanders as well, but the real stars here are Warren and Biden, who effectively have the same fraction of support among Klobuchar supporters. What's more, they lack the high unfavorables seen by Bloomberg and Sanders, who about 30% specifically indicated they'd be dissatisfied with.
Needless to say, Klobuchar telling her backers who to choose is going to make some of this a little easier. And Buttigieg doing the same is likewise a big deal:

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More of Pete's people liked Warren than Biden. This endorsement is massive, particularly because it's a double whammy that can specifically sway the half of Pete's supporters who also liked Amy and the 70% of Amy supporters who also liked Pete to a candidate who is not Warren.
Here's another bit of subtext. Pete and Amy have one thing specifically in common, and it's something that Biden has struggled with: Women disproportionately love them.

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Two candidates that women disproportionately like endorsing Biden ahead of the Super Tuesday primary is important, particularly as a way to make that critical component of the electorate think twice before supporting the only remaining woman in serious contention for the Democratic nomination.