(CNN) Rep. Seth Moulton of Massachusetts endorsed Joe Biden Monday, saying the former vice president "has the experience and judgment not just to win in November, but to lead our nation after he does."

Moulton, a three-term congressman, dropped out of the 2020 race in August and is now the second former 2020 presidential contender to back Biden. Rep. Tim Ryan of Ohio announced his support last year.

"There's no better preparation for the White House than the decades Joe Biden has spent serving the country, especially his eight years as vice president," Moulton said.

"Most importantly: Joe can win. Joe Biden will beat Donald Trump and unify our country after four years of the most reckless commander-in-chief in American history," he added.

Moulton is a 41-year-old Marine veteran who focused heavily on national security and his military service during his presidential bid. He joins a group of veteran lawmakers backing the former vice president, including Reps. Conor Lamb of Pennsylvania, Elaine Luria of Virginia, and Chrissy Houlahan of Pennsylvania.

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