President Obama lambasted Marco Rubio on his home turf on Thursday, slamming the Senator who ran against Donald Trump in the primary, yet later endorsed his controversial candidacy.

“Donald Trump wants to reverse progress,” Obama told the crowd at Florida Memorial University. “Marco Rubio wants to help him.”

Obama refused to give Republicans a great deal of credit for denouncing some of Trump’s nastier controversies, including a leaked tape on which he can be heard bragging about groping women. He instead said their reactions were too little, too late, going so far as to call Rubio’s actions the “height of cynicism” and proof that he would say or do anything to get elected.

“How can you call him a con artist and dangerous and object to all the controversial things he says, and then say, ‘I’m still going to vote for him’?” Obama said. “Come on, man!” Obama repeatedly called Rubio a bad choice for the Floridians in the audience, urging them instead to vote for his opponent, Representative Patrick Murphy, whom he praised as a good leader.

Rubio’s team slammed Murphy in a statement: “Patrick Murphy has accomplished nothing during his four years in Congress — even the President couldn’t think of anything nice to say about him,” Olivia Perez-Cubas, Rubio’s press secretary, said.

Obama also offered a public response to Trump’s statements that he would only accept the results of the election if he were to win on Nov. 8. Suggestions that the vote would be somehow rigged, he said, are not only whining but also dangerous for the country.

“That is not a joking matter. That is dangerous. When you try to sow the seeds of doubt in people’s minds about the legitimacy of our elections, that undermines our democracy,” Obama said.

Obama was in Florida to deliver a speech on the Affordable Care Act, and afterward he stopped by Florida Memorial University for the rowdy speech. The President had been scheduled to attend a rally for Clinton in Florida earlier this month, but it was rescheduled due to Hurricane Matthew.

The President, who already voted early in Illinois, urged early voting in the Sunshine State where a 2013 report found long lines discouraged some 200,000 people from casting ballots. “When you vote early, there are no lines,” he said. “You can take your time.”

“Starting Monday you can reject somebody who proves himself unfit to be President every single day in every single way,” Obama said, urging the crowd to vote early in the battleground state. “You don’t need to wait until Nov. 8 to send Hillary to the White House.”

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