The former First Lady argued that the president wanted to give Americans “complete protection” from competition. He suggested his bombing style during Tuesday’s presidential debate was designed to create this effect.
During the final debate in Cleveland, Ohio, Mr. Trump repeatedly obstructed Mr. Biden and insulted his son.
In return, the Democratic nominee told Mr. Trump to “keep quiet” and called him a “clown.”
Posting on Instagram, Mrs. Obama said: “I feel for you if you stop behaving like a president yesterday. Believe me, I do.
“But we can’t beat him perfectly. This is what he wants.
“So turn those feelings into action – turn them into votes for my friend Joe Biden.
“This is the only way we can get out of this mess and bring some stability back to this country.”
During Tuesday’s debate, Mr. Trump and Mr. Biden clashed over coronavirus, the economy, and other issues related to law and order.
The two had a particularly bitter compromise in the Supreme Court, where the president is trying to replace Justice Ruth Bader Jinsberg, who died earlier this month.
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At the end of the Supreme Court discussion, Mr. Biden sarcastically remarked: “It was really a productive part, wasn’t it?”
Referring to Mr. Trump, he added: “Keep yapin, man.”
In her Instagram post, Mrs. Obama called on Americans to connect with friends and family and encourage them to vote.
He wrote: “You can start by reaching out to everyone you know. Make sure they are registered.
“Make sure they know how and when they are going to vote
“And then follow up with them every day to make sure they cast their ballots.
“Because in this election, we voted for Joe in a number that cannot be denied.”
Mr Trump has repeatedly accused the election of rigging the election by ballot.
As a result he has refused to guarantee he will accept the results.
Mr. Biden is the current favorite to win the November crutch election.