Democrat Mark Kelly, the retired astronaut who is hoping to unseat Republican Sen. Martha McSally in Arizona’s 2020 Senate race, raised $4.2 million during April, May and June, exceeding his first-quarter fundraising.

All told, he has raised $8.3 million since announcing his candidacy in February, and he has nearly $6 million cash on hand, according to his campaign.

More than 85,000 contributors have donated to Kelly's campaign, and more than 90% of his second-quarter donations were less than $100, highlighting his display of strength among small donors, his campaign said.

Kelly's performance likely gives him a financial advantage over McSally, the Republican incumbent who was appointed to the seat once held by Sen. John McCain, R-Ariz.

“We have a tradition of independent leadership here in Arizona and this outpouring of support shows that people are fed up and pitching in to elect a leader who will stand up for our state and what's right," Kelly's campaign manager, Jen Cox, said in a written statement toThe Arizona Republic.

McSally's campaign will release her second-quarter fundraising numbers next week. During the first quarter, she raised $2.1 million.

Neither McSally or Kelly have drawn competitive primary challengers for the marquee 2020 special election to fill the final two years of McCain’s unexpired term.

The race is deemed a toss-up by political analysts and it is expected to draw out-sized national attention and tens of millions of dollars in campaign contributions and outside advertising dollars.

Larry Sabato, the political scientist who directs the University of Virginia's Center for Politics, said Kelly's fundraising is a reflection of his national profile and energy surrounding his campaign.

"He may be one of the very few Senate candidates to outspend an incumbent and that doesn't happen very often," Sabato said. "Kelly is one of the first people mentioned by national Democrats when they talk about their chances of picking up Republican seats — he's usually mentioned first."

Sabato said the key consideration for Arizona's Senate race may be one factor neither candidate can control with money: the result of the presidential race.

In 2016, Trump carried Arizona by just 3.5 percentage points over his Democratic rival Hillary Clinton.

Have news to share about Arizona's U.S. senators or national politics? Reach the reporter on Twitter and Facebook. Contact her at yvonne.wingett@arizonarepublic.com and 602-444-4712.

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