WASHINGTON — When Joe Biden went to Philadelphia late last month for a high-dollar fund-raiser with powerful lawyers and executives on the first day of his presidential campaign, Sen. Elizabeth Warren blasted him.

“How did Joe Biden raise so much money in one day? Well, it helps that he hosted a swanky private fund-raiser for wealthy donors at the home of the guy who runs Comcast’s lobbying shop,” Warren wrote in an email to supporters the next day, April 26.

The Massachusetts senator, a rival for the Democratic nomination for president, hit the same theme over and over for more than a week.

Warren wrote on Friday that her schedule doesn’t include “fancy private fundraising events where only big donors are invited.” Another message said, “Our democracy is not for sale, and neither is my time.”

Some of Biden’s top donors have bristled at the criticism, because they remember attending expensive private events for Warren in Philadelphia as recently as last year.

While she has sworn off such gatherings for her presidential campaign, Warren held fund-raisers for her 2018 Senate reelection bid at a major Center City law firm last year and at the Rittenhouse Hotel in 2017.

Each drew some of the same people who donated $2,800 apiece to attend Biden’s April event at the home of Comcast senior executive vice president David L. Cohen.

For example, former Gov. Ed Rendell and Center City lawyer Stephen Cozen were two of the main organizers for Biden’s Philadelphia fund-raiser, and were also listed as hosts for the Warren event at the law firm Berger Montague on March 12, 2018.

The Warren event sought donations of up to $5,400, the maximum allowed that year.

Rendell donated $4,500 to her Senate campaign and Cozen gave $2,500. Daniel Berger, a managing shareholder at the firm, gave $5,400, while also donating $2,800 to Biden this year, the new maximum allowed in the primary.

Kenneth Jarin, another law partner who served as a host for Biden, called Warren’s attacks “preposterous.”

“I was pleased to support Sen. Warren, I think she’s a terrific senator, but I think it makes no sense for her to criticize Biden for taking checks at the maximum allowed,” Jarin said. “I know that she took lots and lots of $2,700 checks raising money for her Senate campaigns.”

Jarin, who gave $2,800 to Biden and recruited others to do the same, gave Warren $500 when she came to the Rittenhouse Hotel for a 2017 fund-raiser arranged by Peter Buttenwieser, a philanthropist and political donor who died last year. Jarin said that was the typical amount for Buttenwieser’s events.

“Anybody that’s criticizing the Biden-type fund-raiser wouldn’t turn down one if they were offered," said Alan Kessler, a law partner at the Philadelphia office of Duane Morris who went to Biden’s fund-raiser and also attended Warren’s Philadelphia event last year. His firm’s political committee donated $1,000 to Warren, though federal records indicate that amount was later refunded.

Warren has drawn a distinction between fund-raising during a primary against fellow Democrats and in a general election against Republicans, such as her 2018 race or the 2020 campaign against President Donald Trump, when she argues that Democrats can’t afford to “unilaterally disarm.”

She has said she would rather spend her time promoting policies, interacting with voters, and taking questions than soliciting money from big donors.

“Elizabeth decided not to do any closed-door events with wealthy donors because special access for the wealthy and well-connected should not be how we choose the Democratic nominee for president,” a spokesperson, Chris Hayden, wrote in an email. “She believes that this primary is an opportunity to build the kind of grassroots movement that will win the general election and bring real structural change to our government.”

Even while doing some big events for her Senate race, most of Warren’s donations from individuals, about 63 percent, came from those who gave $200 or less. 70 percent of the money she has raised from individuals for her presidential campaign has has come in such amounts, according to campaign filings.

At the same time, she is also reaping the benefits of her big Senate haul: Warren boosted her presidential campaign with $10.4 million from her Senate account.

Her criticism of Biden and the pushback from his supporters reflects some of the broader conflict between rising liberal voices and old-guard pragmatists within the Democratic Party.

Warren, Sen. Bernie Sanders (Ind., Vt.), and others have stressed their appeal to small donors as a sign of their inoculation from corporate influence and the radical change they offer, contrasting themselves with Biden and others with more traditional appeals on both tactics and policies.

Biden supporters argue that campaign money is a realistic requirement for beating Trump.

Berger, the partner whose firm hosted Warren in March 2018, said he didn’t see "any contradiction” between that event and the senator’s current stand.

He noted that his fund-raiser was for a different election, not a Democratic primary, and said it was much smaller than Biden’s, 30 to 40 people.

“At the Biden event, there were people who genuinely support Joe, like I do, for idealistic reasons, and then there were corporate people who were giving money because they have an interest,” Berger said. “There were no such people at the event that I hosted for Warren. These were people who genuinely agree with her on her positions and policy issues.”

Berger said people seeking corporate influence “don’t go to a Warren event. They hate Warren.”

As for himself, Berger said he is ideologically closer to Warren, but wrote a $2,800 check for Biden because he thinks the former vice president has the best chance to beat Trump.

He has also given the maximum allowed to two other Democratic candidates, Sens. Cory Booker of New Jersey and Kamala Harris of California.