(CNN) Democratic Senate candidate Amy McGrath is a former Marine fighter pilot and a fundraising phenomenon. But she enters primary day with an unexpected challenge for the party's nomination.
Long viewed as a shoo-in to progress to a showdown with Republican Senate Majority Mitch McConnell in November, McGrath has increasingly turned her attention to progressive primary rival Charles Booker, a Kentucky state representative gaining momentum -- and national attention -- in the aftermath of the police killings of George Floyd in Minnesota and Breonna Taylor in Louisville, Kentucky. (Mike Broihier, a retired Marine advocating for universal basic income, is also running for the nomination.)
The state hasn't sent a Democrat to the Senate since the reelection of Wendell Ford in 1992. It gave President Donald Trump a 30-point victory in 2016. Neither Democratic candidate would be favored to beat McConnell, the longest-serving Kentucky senator.
But McGrath's supporters believe that she would have a better shot. McGrath has raised over $40 million, an astonishing figure, and commands the support of the Senate Democratic campaign arm, a number of labor unions and others who are drawn to her background as a former fighter pilot who flew in combat for the Marines Corps. They note that her moderate views are more in alignment with Kentucky's traditional electorate than Booker, who supports the Green New Deal (he often refers to it as the "Kentucky New Deal"), universal basic income and "Medicare for All." McGrath in turn favors a public option and a Medicare buy-in for those over the age of 55, rather than overhauling the US health care system with a single-payer program.
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The McGrath campaign has zeroed-in on McConnell, trying to portray him as a Washington swamp monster who cares more about Wall Street and special interests than his own constituents. The McConnell campaign views McGrath as an "extreme liberal" whose campaign will waste millions of Democrats' dollars.
"I'm focused on the message that I have had from the very beginning," McGrath told CNN last week, "which from day one is: we need somebody to take on Sen. Mitch McConnell, who's just going to do what's right for Kentucky and for our country."
But Booker, the youngest Black Kentucky lawmaker at 35 years old, comes from one of the state's poorest zip codes and has argued that his message is uniquely suited to the moment. His role in the protests that followed Taylor's killing, and McGrath's absence early on from anti-racism rallies in Kentucky, has contributed to the notion that the primary could be closer than anyone expected even a month ago.
Booker's campaign has attracted a late groundswell of support -- and with it, small dollar donations -- from progressives across the country, including endorsements from figures like Sens. Bernie Sanders and Elizabeth Warren, who initially signaled support for McGrath, and New York Rep. Alexandria Ocasio-Cortez. Kentucky Sports Radio host Matt Jones, who considered running for Senate, also backed Booker.
The candidates are bracing for a long night, if not a long week, to hear the returns. State elections officials sharply limited the number of in-person polling places from just under 3,700 locations in a typical election to 170 due to the coronavirus pandemic.
Voting rights activists say the changes could result in hours-long lines and the potential disenfranchisement of Black voters. The commonwealth's two most populous counties, Jefferson and Fayette, the homes of Louisville and Lexington, will each have just one in-person polling location open on Tuesday.
Kentucky Secretary of State Michael Adams has pushed back against concerns about the election by noting the number of ballots cast absentee and during early voting. He has also pointed out that the current rules were part of an agreement with Kentucky Democratic Gov. Andy Beshear. Adams' office said Monday that it had issued over 867,311 mail-in ballots in the primary election, while just over half -- 442,919 -- have been returned.
Both Booker and McGrath have seized on the voting issues, but the insurgent challenger has been far more public as he blankets the state and constantly makes himself available to media.
"It's not right. And we've seen in other parts of the country, it's not excusable at all," Booker told CNN. "We are better than this. This is not what democracy is all about. It should be easy to have your voice heard."