During the first Democratic debate last month in Miami, the 38-year-old congressman from California, had urged 76-year-old frontrunner Joe Biden to “pass the torch”.
But despite winning support from activists who praised his decision to campaign around the issue of gun violence and regulation, the congressman failed to make headway in a field of two-dozen Democrats seeking the nomination to challenge Donald Trump.
“Today ends our presidential campaign, but it is the beginning of an opportunity in Congress, with a new perspective shaped by the lives that have touched mine and our campaign throughout these last three months, to bring that promise of America to all Americans,” he told supporters at his headquarters on Monday.
“To believe that it will be the next generation whose leadership will solve climate chaos, bring cures in our lifetime for health care, address the student loan debt crisis and make sure that we say enough is enough, we don’t have to live this way anymore and that we love our children more than we love our guns.”
Earlier, he had written on his campaign website: “After the first Democratic presidential debate, our polling and fundraising numbers weren’t what we had hoped for, and I no longer see a path forward to the nomination.”
Reports say Mr Swalwell, a close ally of Democratic House speaker Nancy Pelosi, will instead seek a fifth term as congressman for California’s 15th congressional district.
Polls showed Mr Swalwell, who had announced his run in April, had failed to gain traction among a field that is probably the biggest in many decades.
A Washington Post/ABC News poll that was conducted from June 29 to July 1, showed him polling at zero per cent among Democratic primary and caucus voters.
He told supporters: “I’m fired up to do that work that I’ve already been doing in the Congress.”
Mr Swalwell has become the first of what will likely be a slew of candidates to depart the race in the weeks ahead.
Politico reported over the weekend that most of the campaigns expect to see only a handful of candidates still in the race by the time of the first primary, the Iowa caucus, on February 3.
It said many Democrats hoped to see a “winnowing of the field”, partly as a means to prevent a drawn out and costly primary, that would merely create an additional financial advantage to Mr Trump.
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