Insider has polled adults nationwide on the 2020 presidential election dozens of times since the end of 2018.

Our polls show that Sen. Elizabeth Warren is the only candidate in the Democratic primary whose satisfaction rate has risen significantly.

On average, affinity for Warren among those aware of her increased by more than 20 percentage points between our most recent polls and those conducted six months ago.

The growth is astronomical compared to the other frontrunners.

Sen. Bernie Sanders' has increased by approximately one percentage point among those familiar with him in the same period, while former Vice President Joe Biden's has fallen by seven percentage points.

Warren's rising popularity corresponds with an increase in faith in her electability. A majority of Democrats now believe that she could win against President Donald Trump.

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In the competitive race for the 2020 Democratic presidential nomination, Sen. Elizabeth Warren of Massachusetts has quickly ascended to what's looking increasingly like clear frontrunner status.

Poll results show that not only is Warren well-liked, but she has also won over significantly more supporters than she had at the beginning of the race — the only campaign to do so thus far.

Since December 2018, Insider has been conducting a series of polls on a regular basis, asking adults nationwide how they feel about the 2020 presidential election. In each poll, self-identifying respondents are asked who they would be satisfied with in the event that they become the nominee.

To see which candidates have gained and lost the most traction among voters, Insider compared the average satisfaction rate of each contender in the most recent month of polling, surveyed weekly from August 30 to September 26, to a month of polling conducted from March 22 to April 27.

Here's how affinity — which we define as the percentage of respondents who are aware of the candidate, and who would be satisfied with them as nominee — for each contender changed in six months, among people who said they would vote in the Democratic primary:

Other frontrunners have failed to win over as many supporters as Warren

Results found that strikingly few candidates have managed to boost their standing since March; the majority have fallen in favor. Compared to other frontrunners, Warren's 21.1 percentage point growth on average in Insider's polls is astronomical.

Sen. Bernie Sanders of Vermont, whose grassroots campaign has far more individual donors than any other contender, with greater latitude around the country, has stayed relatively flat in terms of building affinity, gaining only 1.2 percentage points.

Former Vice President Joe Biden, who has the highest name recognition of any Democratic candidate, and still enjoys the lead in major polls, has lost satisfaction by a drastic 7.1 percentage point downturn.

But some longshot candidates have burgeoning bases

Besides Warren, those who saw noteworthy increases were longshot candidates.

Andrew Yang, an entrepreneur whose presidential campaign centers around a universal basic income program that would provide $1,000 to every American adult, saw an 8.2 percentage point increase in average satisfaction over six months — a rise that has been mirrored in his constituency's expectations of him.

Gov. Steve Bullock of Montana and Rep. Tulsi Gabbard of Hawaii, meanwhile, each had a 6.8 percentage point gain. Both candidates are polling at just 1% in Morning Consult, and Insider's polling has consistently found that most Democrats haven't heard of either candidate. Nonetheless, their gains might mean that their campaigns are starting to ramp up.

A majority of Democrats now believe Warren could beat Trump

Elizabeth Warren's campaign has notably progressed in another way: most Democrats surveyed in Insider's most recent poll said they believe Warren would win against Trump in 2020.

Both Bernie Sanders and Joe Biden command high confidence from voters when it comes to beating Trump, but neither have heightened their support like Warren has.

Six months ago, only 30% of Democrats polled who had heard of Warren believed she could defeat Trump in an election. Now, that figure has nearly doubled, at 59%. The numbers suggest that Warren's campaign is swiftly building momentum — and it's working.

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