Three candidates withdrew from the 2020 Democratic presidential primary in just one week: Gov. Jay Inslee of Washington, whose platform focused on tackling climate change, Rep. Seth Moulton of Massachusetts, who dialed in on his military service, and Sen. Kirsten Gillibrand of New York, whose candidacy emphasized women's rights.

That these three candidates would exit within several days of each other is somewhat remarkable because of a single commonality they share: Based on Insider's polling, the supporters of all three recent 2020 drop-outs really like Elizabeth Warren.

Since December 2018, Insider has been running a series of national polls asking respondents which candidates they would be satisfied with securing the Democratic nomination. Looking at the 10 polls conducted over the course of the summer, people who would have been satisfied with nominee Kirsten Gillibrand were mostly also satisfied with her Massachusetts Senate colleague as nominee as well. The same goes for fellow Bay Stater Moulton and the plan-centric Inslee:

Moulton's sparse support liked Warren 22 percentage points higher than the typical respondent.

higher than the typical respondent. Gillibrand's backers like Warren 24 percentage points more than typical.

more than typical. Inslee's supporters like Warren 27 percentage points more than the typical Democrat does.

Moulton supporters were few and far between and tended to be very open-minded

Let's be blunt: There are not a whole lot of Moulton die-hards in the Democratic primary voting population. While Moulton was in the primary, we got responses from about 6,600 people who said they were registered to vote and would probably participate in their state's Democratic primary. Of those 6,600 people, fewer than a tenth had heard of Moulton, and just 71 said that they'd be satisfied in the event he became nominee. 71 people out of 6,600.

Half of those people were open-minded to the degree that we're not really all that interested in their feelings: 52% were satisfied with 10 or more possible contenders, so they're not exactly choosy.

Nevertheless, the big number for Warren is since May, 78% of Moulton's fans also reported liking her — 22 percentage points higher than her support from Democratic voters overall.

She's followed closely by former Vice President Joe Biden and South Bend Mayor Pete Buttigieg, who each appealed to nearly three-quarters of Moulton supporters.

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Inslee's supporters love Warren, but Castro and Booker are set up to gain too

In polls surveyed from May 17 to August 17, Insider found that 82% of voting Democrats who liked Inslee also felt affinity for Elizabeth Warren. Compared to Warren's overall affection rate of 56% among those who plan to vote in the Democratic primary, Inslee's supporters like Warren 27 percentage points more than the typical Democrat does, preferring her over any other rival in the race.

Warren tweeted a thank you message at Inslee after he announced his exit from the race last Wednesday.

"Climate change is real and it's a crisis — and I will keep fighting alongside you to take bold action before it is too late," she wrote. That may be a bi-coastal alliance to keep on the radar, as no two candidates embraced a campaign based on comprehensive policy proposals quite like Warren and Inslee.

While Warren is the biggest winner from Inslee's departure, other rivals also stand to gain contingents of Inslee's base. These include former HUD Secretary Julian Castro, and Sen. Cory Booker of New Jersey, who were 27 and 24 percentage points more liked by Inslee fans than the average Democrat respectively.

Gillibrand fans liked a whole bunch of other candidates, and Kamala Harris might give Warren a run for her money

Even though Warren is the rival most favored by Gillibrand supporters — liked by 80% of them — those supporters tend to be torn between backing other candidates, weighing seven other options on average.

Among those options, Sen. Kamala Harris is well-positioned for a generous gain from Gillibrand's following. At 78.1% affinity — a 23.7 percentage point uptick from Harris' appeal to the average primary voter — those who supported Gillibrand said they like Harris almost as much as they like Warren.

Sen. Cory Booker has an opportunity to capitalize on Gillibrand's departure as well: He's liked by nearly 65% of Gillibrand supporters — a huge spike compared to his overall performance of 36.9% among typical Democrats.

As with Inslee, Warren tweeted at Gillibrand following her withdrawal from the race, thanking her for her "unwavering commitment to fighting for women."

All three drop-outs failed to get their campaigns off of the ground, and Insider's polling found that Democratic voters had little faith in the possibility of any of them prevailing over Trump in 2020.

The same cannot be said about Warren.

Just about 30% of Democrats though she'd beat Trump in the general when we first polled this, but she's stormed back from the initial preconception to one of the best ratings of the whole race, with about 50% thinking she'd beat the president — 20 percentage points higher than the typical rating.

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