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President Donald Trump on Wednesday questioned why former President Barack Obama has not endorsed Joe Biden, his former vice president and the apparent Democratic presidential nominee.

"I don't know why President Obama hasn't supported Joe Biden a long time ago," Trump told reporters in response to a question at his daily coronavirus briefing. "He feels something is wrong. ... It does amaze me that President Obama hasn't supported Sleepy Joe. It just hasn't happened. When's it gonna happen? Why isn't he? He knows something that you don't know, that I think I know, that you don't know."

Trump later added that Obama has to "come out at some point," because "he certainly does not want to see me for four more years." Obama previously said he would not endorse a candidate until a nominee was chosen. NBC News is characterizing Biden as the apparent nominee at this time.

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Trump did not say what it is he knows that the media does not, but the president has interjected his opinion on the 2020 Democratic primary field before. He also questioned why Sen. Bernie Sanders, I-Vt., dropped out of the race but is keeping his delegates, calling it "a weird deal."

In a tweet Wednesday, he blamed Sanders' primary loss on Sen. Elizabeth Warren, D-Mass., arguing that Sanders would have swept Super Tuesday had Warren dropped out earlier.

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"Bernie Sanders is OUT!" Trump tweeted minutes after Sanders announced that he would suspend his campaign. "Thank you to Elizabeth Warren. If not for her, Bernie would have won almost every state on Super Tuesday!"

Trump also urged Sanders' supporters to flip to support the GOP. "The Bernie people should come to the Republican Party, TRADE!" he tweeted.

Brad Parscale, Trump's campaign manager, also encouraged Sanders' supporters to vote for Trump.

"President Trump is still disrupting Washington, DC, while Biden represents the old, tired way and continuing to coddle the communist regime in China. Democrat elites shoved Bernie Sanders to the side for a second time, leaving many of his supporters looking for a new home," Parscale said in a statement.

Roughly 12 percent of Sanders supporters voted for Trump in the general election in 2016.