Charles Booker has electrified Kentucky politics with a US Senate campaign that upsets expectations, rejects conventional wisdom, and articulates a way to do what no Democrat has ever done: defeat Mitch McConnell in a November election. That’s why the progressive legislator from Louisville, who promises to campaign “from the hood to the holler” for economic, social, and racial justice, now has a real chance of beating the pick of DC insiders for the party’s nomination in one of the highest-profile Senate contests of 2020.

A fresh Data for Progress poll puts Booker at 44 percent versus 36 percent for retired Marine fighter pilot and Democratic primary candidate Amy McGrath, whose “unimaginative and uninspiring” campaign has, in the words of the Louisville Courier-Journal, “fallen flat in these final weeks of the campaign.”

What’s playing out in Kentucky is a story of the power of insurgent politics in the volatile 2020 campaign season.

When Booker entered the primary race against McGrath—a defeated congressional candidate who was recruited by Senate minority leader Chuck Schumer to take on McConnell—he had little name recognition, little money, and little buzz among pundits who barely mentioned his candidacy. The African American legislator quickly distinguished himself as a fearless contender who took bold stands—for impeachment, Medicare for All, and a Green New Deal—and an able campaigner who has delighted in touring the far corners of a state that still elects Democratic governors but has not put a Democrat in the Senate since Bill Clinton was president.

Marching with #BlackLivesMatter activists in Louisville and standing with laid-off coal miners in Harlan County, Booker has mounted a campaign that bluntly declares:

For too long, we have been lied to, robbed, and exploited. Demeaned and disrespected. We’ve been shut out of the decision making process and our voices drowned out by the wealthy and well connected. We’re sick of the corruption. We’re sick of the politicians who ignore us, and the ones who play political games instead of just telling us the truth. We’re Kentucky.

We’re not a tragedy, and we’re not a joke. When we get knocked down, we come back. We don’t wait for folks to tell us what to do. We show them how it’s done. I am not the alternative to Mitch McConnell. WE are.

And as the June 23 election approached, something clicked. Vermont Senator Bernie Sanders heard an echo of his campaign’s “Not me, us!” message and endorsed Booker. So did Representatives Alexandria Ocasio-Cortez and Ayanna Pressley, as well as progressive groups and unions. On Thursday, Massachusetts Senator Elizabeth Warren added her support, announcing that she is proud to “join his fight to root out corruption, dismantle systemic racism, and make big, structural change.”

Booker has also collected endorsements from Kentucky’s two largest newspapers, the Louisville Courier-Journal and the Lexington Herald-Leader; popular sports commentator Matt Jones; legislative leaders from across the state; former Kentucky secretary of state Alison Lundergan Grimes (who ran against McConnell in 2014); and former state attorney general Greg Stumbo. As the final days before the primary ticked down, Booker got another boost with the Thursday release of the Data for Progress poll that put him eight points ahead of McGrath.

The top-line numbers were significant, but that wasn’t the poll’s only good news for Booker. The Civiqs survey of 898 registered voters showed the powerful and enormously well-funded majority leader leading. But in hypothetical contests between McConnell and his leading Democratic rivals, McGrath trailed McConnell 53-33. Booker ran better, narrowing McConnell’s lead to 52-38. Notably, McGrath runs behind presumptive Democratic presidential nominee Joe Biden’s numbers in the poll, and Booker does a bit better than Biden.

This is significant because, while McGrath lost a high-profile congressional race in 2018, Booker is a rising star whom a lot of Kentuckians are still getting to know. Booker’s supporters point to these details as evidence of his potential to build a multiracial, urban-and-rural coalition that says, “It’s time to take back what’s ours and transform our system.”

The prospect that Booker could win the nomination puts a new demand on McGrath and national Democrats.

Progressive groups are urging McGrath, who has raised more than $40 million from across the country for the race against McConnell, to commit to using surplus cash to help beat the majority leader even if she does not win the primary. Early June financial reports showed that roughly $19 million of McGrath’s $40 million haul remained unspent.

“People across America gave millions to Amy McGrath trusting that their money would be spent ousting Mitch McConnell,” explains Joe Dinkin, the national campaigns director for the Working Families Party. “As the race tightens, McGrath owes her contributors an assurance that she’ll use their funds to take on the obstructionist Senate Majority Leader no matter who wins on Tuesday.”

“Legally,” the Progressive Change Campaign Committee notes in a statement, “if McGrath were to lose, she could use excess cash raised for the primary on independent expenditures to defeat McConnell—running one herself or donating to other independent efforts. All grassroots donations of $2,800 or less count as primary election funds. She would be required to return general election money to donors, but that is estimated to be less than $2 million of her cash and could be accompanied with a note urging donors to support anti-McConnell efforts.”

PCCC cofounder Stephanie Taylor says, “Donors don’t want their money going into a slush fund for McGrath’s future campaigns or to bonuses for losing consultants. They don’t even want their money returned. They want to defeat one of the worst senators in history, Mitch McConnell.”