Money poured into Senate contests across the country in the first three months of the year, bolstering some Democrats’ war chests in key races favoring Republicans, including those in which Senator Mitch McConnell, the majority leader, and Senator Lindsey Graham, the chairman of the Judiciary Committee, are seeking re-election.
In Senate contests in states like Kentucky, South Carolina, Kansas and Maine, Democratic candidates raised more money in the first quarter of 2020 than their Republican opponents, according to new filings with the Federal Election Commission.
In their bids to unseat Republican incumbents, some Democratic candidates reported dollar figures that were millions more than what their opponents received. Amy McGrath, Mr. McConnell’s challenger in Kentucky, reported raising over $5 million more than the majority leader did, while Mark Kelly, the Democratic candidate in Arizona, reported raising over $4.5 million more than the Republican incumbent, Senator Martha McSally.
While the Democrats running in reliably red states like Kentucky and Kansas may be betting on long odds, the party has won upset victories in those states in recent years, helping to fuel the hopes of candidates and donors alike.
Over all, many of the Republican candidates still reported having more cash on hand as the races heat up, though the accelerated pace of fund-raising for the Democrats in 2020 suggested new dynamics in some down-ballot races now that the presidential primary campaign has ended.
Ms. McGrath, a retired Marine lieutenant colonel, took in $12.8 million in the first quarter of the year — $5.4 million more than Mr. McConnell did. That amount represented roughly 40 percent of what Ms. McGrath has raised since entering the race last summer.
The two candidates indicated in the federal filings this week that they had roughly equivalent amounts of cash on hand, with Mr. McConnell reporting stores of $15 million and Ms. McGrath reporting $14.8 million.
Ms. McGrath, who received more than twice as much as Mr. McConnell in individual contributions in the first quarter, has been backed by Democrats in Kentucky and beyond who loathe Mr. McConnell’s record in the Senate — especially his central place in helping the Trump administration reshape the federal courts — and are eager to oust him.
In South Carolina, Mr. Graham’s Democratic challenger, Jaime Harrison, a former chairman of the state Democratic Party who has also worked as a lobbyist in Washington, raised $7.4 million in the first quarter, nearly 30 percent more than the $5.7 million Mr. Graham did.
That $7.4 million made up roughly half of what Mr. Harrison has raised since he entered the race last May seeking to be the first Democrat elected in a statewide race in South Carolina since 2006. Mr. Graham’s campaign has a sizable $12.8 million on hand, compared with Mr. Harrison’s $8 million.
Mr. Graham too, has played an instrumental role in the Trump administration’s judicial confirmations as chairman of the Senate Judiciary Committee. As he has positioned himself more closely to President Trump, he has lost his maverick sheen in the eyes of some Democrats.
Barbara Bollier — a Democratic state senator running for the seat that will be vacated by the retiring Republican senator, Pat Roberts — drew more than $2.3 million in the first three months of the year, compared with the roughly $240,000 received by her likely Republican opponent, Kris Kobach, the former Kansas secretary of state and one of the Republican contenders, and the roughly $375,000 received by Roger Marshall, another Republican candidate.
Ms. Bollier, who is hoping to be the first Democrat elected to represent Kansas in the United States Senate in more than eight decades, reported $2.4 million in cash on hand, while Mr. Kobach’s campaign reported having roughly $300,000. Though there was speculation that Secretary of State Mike Pompeo, a former congressman from Kansas, would run for the seat, he told Mr. McConnell early this year that he had decided against it.
Sara Gideon, the Democratic speaker of the Maine House, raised $7.1 million in the first quarter, roughly three times as much as the incumbent Republican senator, Susan Collins, who has come under particular pressure for her vote to confirm Justice Brett M. Kavanaugh to the Supreme Court in 2018.
As her fight to keep her seat continues, Ms. Collins, who has spent more than 20 years in the Senate, has a million dollars more on hand than her opponent — $5.6 million, compared with Ms. Gideon’s $4.6 million, according to the filings.
John Hickenlooper, a Democratic former governor of the state, raised $4.1 million in the first quarter, compared with the roughly $2.5 million raised by the Republican incumbent, Senator Cory Gardner. Mr. Hickenlooper reported having about half as much cash on hand as Mr. Gardner’s $9.6 million.
Mr. Kelly, a Democrat seeking to oust the Republican incumbent, Ms. McSally, took in $11 million in the first quarter, roughly $4.6 million more than Ms. McSally. Ms. McSally, who was appointed to John McCain’s former seat by Gov. Doug Ducey in 2018, has been a staunch supporter of Mr. Trump.
Mr. Kelly, a former astronaut who is married to the former congresswoman Gabrielle Giffords, has deep cash reserves on which to draw: In this week’s filing, he reported having $19.7 million on hand, compared with Ms. McSally’s $10.3 million.