Chicago Mayor Rahm Emanuel had a hard time answering Sunday if Hillary Clinton should run for president again in 2020.

Appearing on CNN's "State Of The Union", Emanuel waffled over the question, ultimately insisting that Clinton "has to decide whether that's in her heart."

Clinton ran and lost to Donald Trump in 2016 in a stunning political upset. She delivered a commencement speech at Wellesley College on Friday, and she took several shots at Trump, including comparing him to Richard Nixon, who ultimately resigned from office.

"If Hillary Clinton is up for another presidential run, would that be a good thing for your party?" CNN anchor Dana Bash asked.

Emanuel was not quick with an answer.

"You know, look, you're asking something that—we're not even first through the midterm election. She hasn't even declared, for me to say that—" he started.

Bash pressed him, but Emanuel insisted that the question was "not a good question."

"You know, I love you," said an increasingly flustered Emanuel. "It's not a good question. OK? So the question is, it's not a good question."

"Why not?" Bash asked. "She sounded like she could be a candidate again. Would you think that's a good idea? You're a party leader."

"I happen to love Hillary, and I think she's full of energy," Emanuel said of Clinton, who was recently overcome by a coughing fit while delivering a commencement address.

He then went on to explain that it didn't matter what was in his head, but rather what was in her heart.

"And I happen to think there's a lot of time between now and the presidential [election], and she has to decide whether that's in her heart," he said. "We have a lot of time between now and the presidential election of 2020. Hillary has a lot to offer. The core question is not whether I think she would be a good candidate. It's whether she wants to run."

"Because," he concluded, "at the end of the day, the public's pretty smart. And if it's only going through the motion, don't pick that up."