Rep. Adam Schiff, D-Calif., called on President Joe Biden to end his reelection bid in a statement to the Los Angeles Times on Wednesday, becoming the 20th congressional Democrat to do so.
"A second Trump presidency will undermine the very foundation of our democracy, and I have serious concerns about whether the President can defeat Donald Trump in November," Schiff, who is running for the Senate, was quoted by the newspaper as saying.
Democrat's concern about the 81-year-old incumbent's ability to beat Republican challenger Trump, or to serve another four years in office, surged after Biden's halting June 27 debate performance.
Former House Speaker Nancy Pelosi, D-Calif., is Schiff's mentor.
Trump is currently in Milwaukee where his fellow Republicans are formally nominating him as candidate, days after he narrowly escaped an assassin's bullet at a Pennsylvania campaign stop.