Former New York mayor Mike Bloomberg, the billionaire businessman who is taking steps to run for president, has launched a $100 million digital ad campaign attacking President Trump in the battleground states expected to determine next year’s election.

The effort will provide a significant boost to Democratic efforts — now totaling at least $325 million in public commitments — to keep the heat on Trump while Democratic candidates battle each other to win the party’s presidential nomination.

“Our thinking is that the general election has already begun,” said Jason Schechter, a Bloomberg spokesman.

The outlay, which far exceeds what any Democratic candidate has raised or spent so far in the race, adds to those of several other outside groups who have devoted money to early swing state campaigns.

Priorities USA, an independent Democratic nonprofit and super PAC effort, has already spent about $7 million of a $100 million campaign for swing state anti-Trump advertising during the primaries. American Bridge, a group that typically focuses on opposition research, launched a $3 million campaign this week focused on rural white voters as part of an effort expected to reach $50 million.

A third group, ACRONYM, which is being advised by former Obama campaign manager David Plouffe, has announced plans for $75 million in digital ads against Trump.

The money is intended to challenge the significant advantages of incumbency in presidential campaigns. Trump’s campaign announced $156 million in cash on hand at the end of September, after raising $125 million in the previous three months.

By contrast, the top fundraising Democratic presidential candidate, Sen. Bernie Sanders (I-Vt.), has raised less than $75 million through the first three quarters of the year. former vice president Joe Biden, who has led national nomination polls this year, has raised less than $38 million in the same nine months.

Trump has also dominated Democratic candidates so far on digital spending. On Facebook, the Trump campaign and its affiliates have purchased $14.7 million in ads this year, according to the social network, compared with $5.45 million by South Bend, Ind., Mayor Pete Buttigieg and $4.3 million by Sen. Elizabeth Warren (D-Mass.).

Much of the early digital spending by candidates is focused on prospecting for more campaign donors, not on persuading swing state voters. An analysis by Priorities USA of recent Trump Facebook ads found that 89 percent of the messages were focused on acquiring new donors and voter information, including spots that ask people to wish Trump a happy birthday or buy campaign merchandise.

“Sometimes you spell ‘desperation’ d-e-m-o-c-r-a-t-s,” Tim Murtaugh, a spokesman for the Trump campaign, said in response to the news of the new Bloomberg digital effort, which was first reported by the New York Times.

A pro-Trump independent effort, the America First Action super PAC and an affiliated group, has announced a fundraising goal of $300 million for the 2020 cycle to defend Trump in battleground states. That spending is expected to focus on Florida, Georgia, North Carolina, Pennsylvania, Ohio and Michigan.

In one Bloomberg ad provided to The Washington Post, Trump’s Twitter feed is highlighted along with the message: “A tweet shouldn’t threaten our country’s security.”

The digital campaign was scheduled to begin Friday, with plans for spending in Michigan, Wisconsin, Pennsylvania and Arizona, according to Bloomberg aides. They said Bloomberg will not appear in the ads, which will nonetheless make clear he paid for them.

“If Mike runs, it is because he believes that Donald Trump is an existential threat, and this demonstrates his commitment to defeating him,” said Howard Wolfson, a senior adviser to Bloomberg.

Bloomberg, one of the world’s richest men, has taken several steps to prepare for a bid for the Democratic nomination, including filing paperwork in states with early deadlines to get on the ballot. He has also been calling top party officials to let them know of his plans.

The move marks a major reversal for Bloomberg, who announced in March that he would not run for president. At the time, he said he was “clear-eyed about the difficulty of winning the Democratic nomination” and would instead focus on spending his money in an effort to hurt Trump’s chances in swing states.

But he and his advisers have since concluded that there is a possible route to the nomination because of lingering divisions in the field and the vulnerabilities of the top-polling candidates.

The decision to reconsider signals, among other things, a public rebuke of ’s performance so far. The former vice president has attempted to build a coalition of the same moderate Democrats that Bloomberg would court.