Rep. Eric Swalwell dropped out of the 2020 presidential race Monday after struggling to break out in a jammed Democratic primary field.

The four-term congressman from California will instead run for reelection to the House. He becomes the first presidential candidate who made the first debate cut to leave the race. Swalwell said he dropped out in part due to poor fundraising and polling numbers.

"Today ends our presidential campaign," Swalwell said during a news conference Monday. He added that "if there was a viable chance" for him to win the nomination, he "would not be standing here today."

There are still about two dozen candidates in the race for the Democratic nomination. Fundraising and polling thresholds for qualifying for debates starting in September will become more difficult, meaning the field could start to narrow in the coming months.

Swalwell, 38, ran on a gun control platform and cast himself as a younger alternative to candidates such as former Vice President Joe Biden and Sen. Bernie Sanders, I-Vt. But he struggled to stand out in a field of about two dozen Democrats. The congressman often failed to register as the first choice for any respondents in early polls of the 2020 primary.

Swalwell could face a primary fight to keep his seat in California's 15th District. Aisha Wahab, a Democratic city council member in Hayward, outside of Oakland, has already entered the race.

Asked Monday about the potential for a competitive primary, Swalwell said, "I don't take anything for granted."

"I hope the district sees that these issues I was running on nationally were the district's issues," he said. The congressman added that he has not spoken to Wahab but welcomes "anyone who wants to run."

It may not take long for another Democrat to get into the race after Swalwell's departure. Multiple outlets reported that billionaire investor Tom Steyer has privately told friends he plans to enter the 2020 race.

Steyer has piled millions of dollars into an effort to build support for President Donald Trump's impeachment.

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