One of the most striking storylines of the current midterm election cycle has been Republican vulnerability in states and districts once considered safely red that have turned into genuine toss-ups amid President Donald Trump’s unpopularity. On Tuesday, a new report highlighted why the GOP should be deeply concerned about its Senate race in one such state, Kansas, where the Republican Senate candidate initially failed to meet the criteria to participate in a debate — for a surprising reason.

“Wow,” posted Kansas political strategist Tyson Brody. “The Kansas City Star confirms that less than 25 percent of Roger Marshall’s campaign fundraising comes from Kansas, failing the participation criteria for a Nexstar debate.”

The disclosure carries profound implications for Sen. Roger Marshall (R-KS), who polls show is slightly trailing his Democratic opponent, pastor Adam Hamilton. Participation thresholds tied to the share of money raised in-state are typically designed to test whether a candidate has genuine support among the voters they hope to represent — and Marshall’s haul, with less than a quarter of it originating from Kansas, fell short of that bar. The two previously shared a stage at what the Star described as “the boisterous Kansas State Fair forums earlier this month, where Marshall faced down a hostile crowd that at one point cut him off mid-answer with chants of ‘shame on you.’”

Since that encounter, it has been an open question whether another debate would take place, given Marshall’s extraordinarily high level of out-of-state funding. The senator’s lack of local donations suggests dwindling support within the state, even as outside financial backers attempt to influence the election’s outcome. A fundraising base concentrated outside a candidate’s home state is precisely the kind of detail opponents seize on to argue that a lawmaker answers to national donors rather than the voters who would send him back to Washington — a line of attack Hamilton’s campaign leaned into directly. Ultimately, organizers decided Marshall could participate after determining that there was “significant public interest served by the inclusion of the incumbent United States Senator.”

“In light of Nexstar graciously making a public interest exception to allow incumbent Senator Roger Marshall to qualify for the debate, Adam Hamilton will plan on joining the FOX4 debate — despite Senator Marshall failing to meet the in-state fundraising criteria and instead raising all his money from corporate PACs,” said a statement from Hamilton’s campaign. One of his spokespersons added: “After clearly winning the State Fair debate, Adam looks forward to debating Sen. Marshall again.”

The news out of Kansas comes as the GOP struggles to fend off what Republicans fear will be a massive blue wave in November. While the state currently has a Democratic governor, it has not elected a Democrat to the Senate since 1932. If Marshall loses, it would break the longest current single-party Senate streak held by any state in the United States — a milestone that helps explain why even a slight polling deficit in a state of this political makeup has set off alarms well beyond Kansas’s borders.

Republicans recently told The Hill that internal GOP polling has put the party on red alert over the possibility of losing Kansas, where voters in general are angry about the war with Iran, and farmers in particular are outraged over skyrocketing diesel prices and Trump’s decision to import beef. As one senator told The Hill anonymously, “It’s a tough environment,” and things are looking “grim” for Republicans.

With the debate now set to proceed under the public-interest exception, the coming weeks will show whether Marshall can reset the narrative on stage — and whether the concerns voiced in the party’s own internal polling are borne out at the ballot box in November.