Democrat Jon Ossoff will report raising more than $1 million for his U.S. Senate bid over the last three months as he races to establish himself as the frontrunner in a contest with three other well-known contenders competing to challenge Republican David Perdue.

Ossoff told The Atlanta Journal-Constitution that his fundraising haul includes contributions from more than 19,000 donors who made about 30,000 contributions, including roughly 96% that were under $200. He also said he added nearly 8,000 new donors who had not given to his 2017 campaign for a U.S. House seat.

The Ossoff campaign did not release how much cash it has in its account. He reported in October roughly $1.3 million in cash on hand, the most of any Democratic rivals in the race.

He’s the first leading Senate candidate to reveal their fundraising for the quarter, which spans from October through December. The dash for cash serves as an important test of campaign strength to the donors, party officials and activists closely watching each contest.

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In his bid for a second term, Perdue has so far posted the biggest numbers by raising about $2.4 million in the last three-month fundraising quarter. He reported roughly $6.3 million in his campaign account through September, but has not yet released his latest figures.

Ossoff has emerged as his most formidable fundraising rival. The investigative journalist collected about $800,000 in a three-week span since entering the race, relying on the donor network he built during his unsuccessful House campaign in 2017 and appeals by top allies.

Among them is U.S. Rep. John Lewis, the Atlanta Democrat who was one of his first endorsements. Lewis sent a December fundraising appeal, shortly before announcing his cancer diagnosis, saying that Ossoff’s election is “my highest priority.”

“I’ve known Jon for many years,” he said in a note to Ossoff donors. “This bright young leader is like a brother to me. I’m ready to travel to all of Georgia’s 159 counties to campaign for him.”

Ossoff’s earlier disclosure, in October, amounted to roughly the same amount of campaign cash as his three top Democratic rivals – business executive Sarah Riggs Amico, Clarkston Mayor Ted Terry and former Columbus Mayor Teresa Tomlinson – raised combined during the same three-month quarter.

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That trio of candidates has yet to disclose their finances for the latest fundraising period. Tomlinson raised about $380,000 during the last quarter, while Amico collected about $310,000 and loaned her campaign another $400,000. Terry took in about $90,000 during that timeframe.

Each also faces more competition to collect cash this year, as White House hopefuls target Georgia donors and a race for the state’s other U.S. Senate seat takes shape. Republican Kelly Loeffler will take office on Monday, and party leaders are still seeking to recruit a candidate to challenge her.

Only one well-financed Democrat has entered the contest: Matt Lieberman, the son of former U.S. Sen. Joe Lieberman who said he’s raised more than $250,000 in the weeks since his October announcement but has not disclosed his full amount.