Massachusetts Sen. Elizabeth Warren spent most of the spring as the Democratic presidential hopeful on the rise.

Her poll numbers steadily ticked up, as she carved out a spot as a policy-focused candidate whose weekly plan rollouts set much of the broader campaign agenda.

The momentum translated to fundraising. Warren took in $19.1 million in April, May and June — more than three times what her campaign raised during the first quarter of 2019, according to her campaign Monday.

The fundraising total is about $1 million more than Vermont Sen. Bernie Sanders raised, and about $7 million more than California Sen. Kamala Harris' second-quarter total.

Bernie Sanders attends the Fourth of July parade in Pella, Iowa. In polls and fundraising, Sanders is starting to be surpassed by fellow progressive Elizabeth Warren. (Joshua Lott/Getty Images)

Warren's second-quarter fundraising trails only former Vice President Joe Biden and South Bend, Ind., Mayor Pete Buttigieg, both of whom devoted considerable time to attending high-dollar fundraisers across the country. Warren, by contrast, has made the unusual move of forgoing fundraising events.

That decision seemed to hurt her first-quarter fundraising, when several other candidates raised more money than her. But, as Warren made more headlines in the spring, the online donations outpaced most of the 2020 field.

"To sum it up: we raised more money than any other 100% grassroots-funded campaign. That's big," said campaign manager Roger Lau in an email to supporters announcing the fundraising totals.

The average Warren donation was $28, according to the email.

We don't get a full picture of Warren and other candidates' finances until mid-month, when full campaign finance reports will be filed with the Federal Elections Commission.

Campaign contributions are a rough indicator of which candidates have widespread support among Democratic voters. They also show which campaigns will have the staff and advertising resources needed to compete in a crowded primary field.

The Democratic National Committee uses raw donor totals as one metric to decide which candidates qualify for televised debates. Candidates will need at least 130,000 donors to make the stage in September. Warren's campaign says more than 364,000 people contributed to her campaign during the second quarter alone.

Warren has also emerged as a threat to Sanders' candidacy. She is essentially tied with Sanders in an average of the national polls, but also has overtaken him in some early state surveys, notably in Iowa and South Carolina.

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