Democratic 2020 presidential hopeful and billionaire activist Tom Steyer (L) gestures at fair visitors at the Iowa State Fair in Des Moines, Iowa on August 11, 2019

Steyer's campaign shelled out $2.9 million on Facebook ads in the 30 days from July 13 to Aug. 11, according to the company's ads archive. The total nearly tripled the next biggest spender in the Democratic field — Sen. Kirsten Gillibrand, a New York Democrat whose campaign put just more than $1 million into Facebook ads during the same period.

Steyer, known for funneling millions of dollars into a push to impeach President Donald Trump, took a unique path to the cusp of qualifying for the debates. He entered the presidential race in July — months later than most of his rivals — pledging to spend $100 million of his own money on his bid. He then blanketed Facebook with ads — many of which urged supporters to donate $1 to his campaign.

The former hedge-fund manager and activist reached the 130,000 individual donor mark required to make the debate stage in Houston next month. Steyer now needs to garner 2% of support in one more qualifying poll to join nine other Democrats in the debate. Candidates have until Aug. 28 to qualify.

After piling money into ads, billionaire Tom Steyer has hit the donor requirement for the next 2020 Democratic presidential debate, his campaign said Tuesday.

If Steyer ends up making the debate stage, some of his rivals will likely target him as an example of the corrosive influence of money in politics. On Tuesday, Montana Gov. Steve Bullock — who is struggling to make the third debate — tweeted that Steyer spent millions "to buy his way onto the debate stage."

"But no matter what the [Democratic National Committee] says, money doesn't vote. People do," Bullock said. The Steyer campaign did not immediately respond to a request to comment on Bullock's criticism.

Bullock tweet: Tom Steyer spent nearly $10 million to buy his way onto the debate stage. But no matter what the @DNC says, money doesn't vote. People do.

When Steyer jumped into the race last month, Sen. Elizabeth Warren, D-Mass., tweeted that the "Democratic primary should not be decided by billionaires, whether they're funding Super PACs or funding themselves."

Elizabeth Warren tweet: The Democratic primary should not be decided by billionaires, whether they're funding Super PACs or funding themselves. The strongest Democratic nominee in the general will have a coalition that's powered by a grassroots movement.

At the time, Sen. Bernie Sanders, I-Vt., also told MSNBC that he was "a bit tired of seeing billionaires trying to buy political power."

Democrats can qualify for the debates through surveys taken nationally or in the key early voting states. All of Steyer's polling success so far has come at the state level.

He topped 2% of support in two separate surveys in Iowa, which will hold its first-in-the-nation caucuses in February. He also reached 2% in a poll of South Carolina, where the fourth nominating contest will take place in late February.

Steyer has put some focus on messaging in the early states. He spent $1.4 million on a television ad campaign that ran from July 10 to July 23. It aired nationally and in Iowa, New Hampshire, Nevada and South Carolina.

His campaign put another $500,000 into TV ads that ran nationally and in the early states during the second set of Democratic debates on July 30 and July 31. His campaign did not immediately respond to a request to comment on how much it has spent on television since.

Steyer just completed his first campaign swing through Iowa. He also made stops in New Hampshire and South Carolina in July.

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