While making an appearance in Florida on Thursday to campaign for Democratic nominee Hillary Clinton, President Barack Obama took time on the stump to criticize Florida Sen. Marco Rubio, saying his continued support for Trump makes him unworthy of re-election and urged Florida voters to send Democratic Rep. Patrick Murphy to the Senate instead.
Rubio lost the Republican presidential nomination to Trump after a bitter primary campaign, during which he called Trump a "con artist," among other things.
The senator has said he supports Trump's bid for the White House, despite their policy disagreements and recent accusations that Trump has been sexually aggressive toward women, because he doesn't want Clinton to be president.
Obama said such reasoning shows that Rubio cares only about himself.
"How can you call him a con artist and dangerous and object to all the controversial things he says, and then say 'but I'm still going to vote for him.' Come on, man," Obama said. "It is the height of cynicism."
When it came to Trump, Obama said that the Republican nominee's attempt to "sow the seeds of doubt" about the integrity of elections in America was "dangerous," undermines U.S. democracy and does the work of the nation's adversaries.
"That is not a joking matter," Obama said.
During the final presidential debate with Clinton on Wednesday night, the Republican candidate refused to say whether he would follow years of tradition and concede if he doesn't win the White House on Nov. 8. He has laid the groundwork by complaining for weeks that the system is "rigged" against him and in favor of Clinton, a former first lady, former U.S. senator and former secretary of state.
"I will tell you at the time. I'll keep you in suspense," Trump said. Clinton responded by calling the statement "horrifying."
On Thursday, Trump tried to make light of the situation while campaigning in Ohio.
"I would like to promise and pledge to all of my voters and supporters and to all of the people of the United States that I will totally accept the results of this great and historic presidential election," he said. After pausing for several seconds, Trump added: "If I win."
Obama, who has felt the sting of losing an election, wasn't buying it. He said Trump's comments were further evidence that he's unfit for office.
"All the Republicans — not all, but most — have acknowledged there's no way to rig an election in a country this big," Obama said. "He doesn't even worry if what he says is true. This is just about him worried that he's losing, which means he really doesn't have what it takes to hold this job."
He said Trump didn't offer a "shred of evidence" to prove rigging or fraud, and called the claim "more than just the usual standard lie."
Obama urged Floridians to take advantage of the opportunity to vote early, beginning on Monday.
"There's only one way we lose this election. Just one. If we don't turn out to vote," Obama said. "Only way. We got to do it big. We got to leave no doubt."
Obama said Trump is the first major party nominee in U.S. history to suggest he will not accept a loss.
"That is dangerous," Obama said. "Because when you try to sow the seeds of doubt in people's minds about the legitimacy of our elections, that undermines our democracy. ... You're doing the work of our adversaries for them because our democracy depends on people knowing that their vote matters, that those who occupy the seats of power were chosen by the people."
Earlier in the week, Obama advised Trump to "stop whining" and get to work trying to win votes.
After the rally, Obama ventured to Miami Beach to attend a fundraising dinner for Democratic gubernatorial candidates. About 40 people were expected to attend the event, which was closed to news media coverage.
Based on reporting by The Associated Press.