Sen. Maggie Hassan (D-N.H.) was initially seen as one of the most vulnerable Senate Democrats up for re-election this year. But as New Hampshire’s Sept. 13 primary draws closer, there’s still no clear Republican frontrunner to take her on in November.

Why it matters: The GOP establishment’s failure to coalesce around one viable candidate after its initial favorite — New Hampshire’s current Gov. Chris Sununu — decided not to enter the race has helped clear the way for Democratic incumbent.

“Sununu’s decision to forego the Senate race turned the race from a slam dunk into a coin toss,” Ken Spain, a Republican strategist and former GOP campaign official, told Axios.

“New Hampshire falls into the growing category of races where Republicans are relying on the political environment to carry some of their candidates across the finish line.”