The Clinton campaign is gearing up for Donald Trump “to bet everything on one final, major attack,” according to a fundraising email sent Monday morning by campaign manager Robby Mook.

Mook has come to this conclusion, he writes, because Trump has raised a ton of money but hasn’t spent anything on TV ads.

“Last month, Trump and the GOP raised over $80 million. And he hasn’t spent one dollar on any TV advertising. I’m not exaggerating — literally since the general election began, he hasn’t spent any money whatsoever on one of the most critical components of a winning campaign,” Mook writes.

“We have to anticipate that Trump’s going to spend big in the last lap of this race — and we know that a flood of money in the final few weeks could undermine all the work we’ve put in to build this campaign,” he ads.

But Mook believes that despite the coming attack, Clinton will win the presidential election.

“We’re going to win decisively. We’re going to earn a mandate to govern,” Mook stated.

The Clinton campaign manager is asking for a $1 donation to help prepare for the coming onslaught.