Donald Trump takes Kanye West seriously.

In an Oval Office interview Tuesday, the president told RealClearPolitics he has been watching intently as the music mogul mulls a bid for the White House. The two are friendly, and Trump welcomed him to 1600 Pennsylvania Avenue before the 2018 midterms. They haven’t talked about presidential ambitions.

And West has not registered as a candidate or put together a campaign committee or taken any of the traditional steps involved with a run for office. He has only tweeted.

“We must now realize the promise of America by trusting God, unifying our vision and building our future,” West wrote on the Fourth of July. “I am running for president of the United States,” he declared before adding the hashtag “2020Vision.”

This leaves everyone, including Trump, wondering whether West will actually do it.

“He may. It’s very interesting,” the president said from behind the Resolute Desk before noting that the artist, who famously and controversially donned a red MAGA hat in the Oval Office, has “a real voice.”

West, shown above meeting with Trump in October 2018, needs to work on his timing, though.

As Trump noted, the window of opportunity may have passed: “It’d have to be limited to certain states because in some states the deadline has been missed.”

But the celebrity president does not object to having another celebrity on the ballot in November 2020 and then again in November of 2024. “If he did it,” Trump said, “he would have to view this as a trial run for what’s going to happen in four years.”

It was retweeted more than half a million times, and liked more than a million times.

But presidential campaigns take time and planning, not just viral moments. Usually candidates begin laying the groundwork years before formally announcing a run. West would have just four months, and for that reason many are tempted to dismiss his political flirtation as a stunt. But his money and his name recognition, combined with political arithmetic, could make him a factor.

As some have already noted, Trump won his first term with a straight flush and by narrow margins in midwestern states. He won Michigan by 10,000 votes, while election officials recorded nearly 9,000 write-in ballots there. He also won in Wisconsin by 23,000 votes. Meanwhile, voters wrote in the name of another candidate 35,150 times.

If the rapper actually means what he tweets, then those numbers should make campaigns nervous. The president seemed relaxed Tuesday morning though, and likely with good reason.

While West has publicly backed Trump in the past, he isn’t likely to steal away many voters on the right. He said in a May 2018 interview with radio host Charlamagne Tha God that his presidency would be a mix of “the Trump campaign, and maybe the Bernie Sanders principles.”

“I think both are needed,” the rapper added.

At least in theory, an independent bid by West could also throw the youth vote into flux. While Millennials generally skew Democratic, a vocal contingent has made known its unhappiness with Joe Biden. This bloc could find an alternative in the popular musician, sapping votes away from the left in a close election.

This would certainly please the president, though he didn’t address any strategic details other than to say that a Kanye West candidacy in 2020 “would be a great trial run.”