“I dream about Biden. That’s a dream,” Trump said. “I’d love to have it be Biden.”
Biden, a former senator from Delaware, unsuccessfully sought the Democratic presidential nomination in 1988 and in 2008, both times dropping out after poor showings.
That was evidence, Trump said, that Biden “by himself could never do anything.”
“President Obama took him out of the garbage heap, and everyone was surprised he did,” Trump said.
Biden considered a third presidential run in 2016 but decided against it, saying his family was still recovering from the death of his son, Beau, from brain cancer.
Earlier this week, Biden said he would make a decision about a 2020 presidential bid by January.
“I know I have to make up my mind, and I have to do it by January,” Biden said at a forum in Bogota, Colombia.
Biden has not been shy about criticizing Trump. Following Trump’s news conference this week with Russian President Vladimir Putin, Biden called Trump’s performance “beneath the dignity of the office of the president.”
In a poll last month, Biden led the field of potential 2020 contenders, with 32 percent support from Democrats in the survey by Harvard University’s Center for American Political Studies and the Harris Poll.
Hillary Clinton, the party’s 2016 nominee, was second, followed by Sen. Bernie Sanders (I-Vt.), the runner-up in the 2016 Democratic nominating contest.