Speaking on ABC's "This Week," Richardson declared Biden has "always wanted to be president."
He continued: "I think he would run. Hillary Clinton would be formidable, no question about it, but I’ve known Biden over the years. He is somebody who's always wanted to be president. He’s got the eye of the tiger."
Richardson was the U.S. ambassador to the United Nations under President Bill Clinton. He supported Barack Obama for Democratic presidential nomination in 2008.
He described Clinton as a formidable candidate "who not only is appealing to the Democratic base, but is appealing to a Republican base that acknowledges the great work she did."
Clinton insists that her days of running for office are over. However, the current Irish American VP has not done much to dispel rumors that he’s considering a presidential run.
"It’s no secret that he’s thinking about this," his son, Beau Biden, recently told The New York Times.
"I’m glad he’s thinking about this. But he hasn't made up his mind."
Clinton supporters recently launched a Ready For Hillary PAC which has the backing of Democratic strategist James Carville.
Speaking on "This Week" on Sunday, Carville argued that American politics hasn't seen as strong a front-runner in generations.
"There has never been a front-runner, a non-incumbent front-runner, like her since probably Eisenhower," Carville said.