Obama’s highest numbers were among the young voters Remain knew was with them but feared wouldn’t vote — a YouGov poll taken during the vote showed 75 percent of voters 18-24 were with Remain, as opposed to 39 percent among voters 65 and older.

Remain operatives milked that every way they could, adding a youth town hall to Obama’s schedule and a meeting with Labour opposition leader Jeremy Corbyn, who’d proven a consistent pain from the start.

“What it did was say to young people who love him the most, ‘Start to pay attention,’ ” the Remain operative said.

“Cameron couldn’t speak to the young people, Corbyn wouldn’t—Obama could.”
Remain operatives attribute the uptick in youth voter registration to Obama’s visit. Without that, they say (and the White House agrees), the vote would probably have been worse for the White House.