Democrat Teresa Tomlinson pulled in more than a half-million dollars during the first three months of her bid to unseat U.S. Sen. David Perdue.

The former Columbus mayor is set to announce Sunday she raised roughly $520,000 and loaned herself another $30,000 between April and the end of June. She has about $330,000 in cash on hand.

The second quarter campaign finance report is notable because it's the public's first peek at Tomlinson's finances since she filed the paperwork to run in early April. She's trying to portray herself as the Democratic frontrunner in an unsettled race that's likely to attract at least one more major contender.

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Tomlinson’s campaign said it raised money from roughly 3,500 individual donors from all 50 states, and that nearly three-quarters came from inside Georgia. Still, the numbers are a small fraction of the $22 million her team believes it needs to deny Perdue a second term.

They also contrast with other Democratic Senate candidates in competitive states who took in larger amounts over the same time period. At least six Democratic challengers have announced seven-figure fundraising results for the second quarter, according to the Center for Responsive Politics.

Tomlinson spokeswoman Nicole Henderson said the contributions show that voters believe in “Tomlinson's leadership and this campaign's ability to send a Democrat from Georgia to the U.S. Senate."

She also cautioned the figures could change before they are posted later this month by the Federal Election Commission.

Read more: A Stacey Abrams-less Georgia Senate race is about to heat up

Fundraising numbers aren’t directly indicative of public support, but they help provide a sense of a candidate’s political momentum. A hefty haul can also scare off potential competitors, though Tomlinson is likely to face a rival regardless.

Logistics executive Sarah Riggs Amico, who ran unsuccessfully for lieutenant governor last year, is expected to launch her campaign within weeks. And former 6th District candidate Jon Ossoff is eyeing the seat.

Higher-profile candidates, including gubernatorial runner-up Stacey Abrams and former acting U.S. Attorney General Sally Quillian Yates, have passed on a bid, frustrating national Democrats who were hoping to attract a mega-watt political star to challenge Perdue.

Tomlinson has seized on the opening. She filed paperwork in early April to start raising cash for the race, but said at the time she would only run if Abrams did not. She started fundraising in earnest in May, shortly after Abrams passed on a bid.

National Democrats see Georgia as crucial to flipping control of the U.S. Senate, and they’re eager to build on their recent successes across metro Atlanta’s suburbs. But Republicans, who haven’t lost a statewide race since 2006, hope an election-year surge will fuel Perdue’s re-election.

The first-term Republican is a close ally of President Donald Trump, Gov. Brian Kemp and former Gov. Sonny Perdue, who is his first cousin. A formidable fundraiser, the Republican pulled in nearly $1.8 million during the first quarter of 2019. He has yet to disclose his second-quarter figures.

Read more: Who could challenge Sen. David Perdue in 2020