Businessman Andrew Yang, a political novice and outsider candidate in the Democratic presidential race, raised $10 million in the past three months — more than tripling his haul in the previous quarter, the campaign said Wednesday.

Yang outraised two sitting U.S. Senators who also announced their third-quarter presidential campaign fundraising totals Wednesday: Sen. Cory Booker of New Jersey and Sen. Michael F. Bennet of Colorado.

Booker’s campaign said he raised $6 million, thanks to a surge of donations in the final 10 days of the quarter, after a major public fundraising push to boost his quarterly total.

Bennet’s campaign raised $2.1 million in the third quarter, on par with his total the previous quarter.

The campaigns’ official fundraising figures will available when they file their reports with the Federal Election Commission on Oct. 15. Those reports will cover their campaign fundraising and spending from July 1 through Sept. 30.

Yang’s boost in fundraising came amid a series of public appearances that caught attention on social media and drew in new supporters. Of his quarterly haul, $2.4 million came from donors purchasing merchandise, the campaign said, including hats carrying a favorite campaign phrase among his supporters: “MATH,” which stands for “Make America Think Harder.”

A flurry of new online supporters flocked to Yang in response to his public gambit at the September Democratic debate: His plan to give away $1,000 a month to up to 10 randomly selected families for a year in an effort to demonstrate the impact of his signature policy proposal, the universal basic income.

Some campaign finance experts have said the giveaway is a legally dubious use of his campaign funds. Nonetheless, the campaign collected more than 450,000 email addresses of people entering the raffle online, and collected $1 million in 72 hours after the debate, Politico reported.

It is unclear when the lottery will begin. The campaign has until Nov. 30, 2020 — after Election Day — to announce contest winners, according to the rules.

Yang’s campaign entered the fourth quarter with $6.3 million in cash, officials said. The campaign plans to open new offices in Nevada and South Carolina and hire new staffers there in the coming weeks, they said.

Booker benefited this quarter by publicly pleading with supporters to help keep his candidacy viable by meeting his fundraising goal.

The 10-day push for donations netted $2.2 million, the campaign said — more than one-third of his quarterly total. Through a blog post Wednesday, Booker announced his fourth-quarter goals for raising and spending money.

Bennet entered the fourth quarter with $1.8 million in cash, officials said. Bennet, who has not qualified for the October Democratic debate, has launched ad campaigns in Iowa.

Three other Democratic candidates have released their third-quarter totals so far: Sen. Bernie Sanders of Vermont ($25.3 million); South Bend, Ind., Mayor Pete Buttigieg ($19.1 million); Sen. Kamala D. Harris of California ($11.6 million).