MANCHESTER, N.H. – Donald Trump crossed paths with his political nemesis President Barack Obama on Monday, the final day of his improbable White House campaign, a campaign Obama himself may have sparked five years ago.

Trump returned to New Hampshire, a sentimental favorite after its February primary gave him his first ever election victory. That victory ushered in more early wins that in two months let him lock up the Republican nomination.

“New Hampshire has never disappointed me. Remember the primaries?” he asked thousands of cheering supporters in Manchester’s SNHU Arena.

Just hours earlier and 30 miles to the east, Obama packed an arena at the University of New Hampshire’s Durham campus, where he kept up his attacks on Trump as an incompetent know-nothing who lacks impulse control.

“Over the weekend, his campaign took his Twitter account away from him,” Obama said with a laugh. “If your closest advisers don’t trust you to tweet, how can you trust him with the nuclear codes?”

Monday wasn’t the first time the two were in the same vicinity. Obama and Trump were both in Jacksonville, Florida, on Thursday, and in Miami the week before. And it’s something Trump has noticed, and it gets under his skin.

Almost daily in recent weeks, Trump has complained in speeches and tweets that Obama is campaigning for Democratic nominee Hillary Clinton rather than spending the whole day at the White House. He complained about it again Monday. “We’ve got a president who all he wants to do is campaign for Crooked Hillary,” he said, departing from his script. “What a joke. What a joke. He shouldn’t be out campaigning.”

He also complained, as he often does, of Obama’s use of the Boeing 747 that is primarily used as Air Force One and how wasteful it is. Trump over the years and over this campaign has made it clear how fond he is of his own Boeing 757. In an interview with Rolling Stone last year, he even ― incorrectly ― claimed it was larger than Air Force One.

The New York Times reported this week that seeing the much larger aircraft parked near his own in Miami angered Trump to the point of his insisting on an insulting tweet, which his press aide softened before hitting send.

Irritation with Obama’s bigger, taxpayer-funded ride appears to be another manifestation of Trump’s resentment of Obama that’s likely rooted in the White House Correspondents’ Association dinner in 2011, which came shortly after Obama shot down Trump’s untrue claims that Obama may have been born outside the United States, which would have made him ineligible to become president. Obama blistered Trump from the dais, ridiculing his reality TV show and, more broadly, his ego. Trump could do little but sit with a forced smile, but those seated nearby reported that he was livid.

Longtime Trump friend and former campaign aide Roger Stone has speculated that it was that particular moment when Trump decided he would run for the presidency.

If Obama was in fact that trigger, he has been working hard to undo that unintended consequence in recent months. As late as this spring’s White House Correspondents’ Association dinner ― which Trump did not attend ― Obama treated him as a laughing matter, joking that Trump was probably only looking for free publicity for his hotels when he instead wound up as the Republican presidential nominee.

Obama on Monday was making it clear he was no longer joking. “Donald Trump is uniquely unqualified to hold this job. And the good news is, New Hampshire, you are uniquely qualified to make sure he does not get this job. But you’ve got to vote. You’ve got to vote tomorrow.”

Obama’s New Hampshire visit was the third campaign appearance on behalf of Clinton on Monday, after one in Ann Arbor, Michigan, and just before a joint appearance with Clinton and first lady Michelle Obama in Philadelphia.

Trump’s New Hampshire stop was his fourth rally of the day, following appearances in Sarasota, Florida; Raleigh, North Carolina; and Scranton, Pennsylvania. His last appearance was to be in Grand Rapids, Michigan, near midnight.

Both Clinton and Trump plan victory parties in New York City on Tuesday evening.

CORRECTION: An earlier version of this post misidentified the venue where Obama spoke as a basketball arena.