Inside the rift that could define the future of Pennsylvania politics

John Fetterman was angry.

The Democratic senator from Pennsylvania was readying to speak at a disaster response press conference in Bucks County on July 16, 2023, just hours after flooding in Upper Makefield that ultimately killed seven people. Local officials spoke for a few minutes to offer an initial update for the assembled press. Then, Gov. Josh Shapiro provided information on what his administration was doing to respond to the emergency.

After a few minutes, Shapiro tossed the microphone back to the local responders — not Fetterman. Moments later, the event wrapped without Fetterman ever speaking.

Already deeply skeptical of Shapiro, Fetterman swore off appearing at events alongside the governor going forward, as three sources familiar with the incident told NBC News.

Fetterman went “through four or five rounds of prep on the run of show for that,” one source said. “And [Shapiro] just sidestepped it completely. After that, John [said]: ‘If there’s an event where he’s going to be there, I don’t want to do it.’”

A person familiar with the event said the idea Shapiro intentionally sidestepped Fetterman was "inaccurate."

"When it came to providing updates in the face of this emergency, local officials were leading the response and determined the run of show," this person said.

The episode highlighted what has become an increasingly volatile relationship between Pennsylvania’s two most ambitious elected officials. It’s a Democratic Party rivalry that is suddenly spilling out into full view and has the potential to shape state politics — and maybe even the national political scene — for years to come.

Earlier this month, as Vice President Kamala Harris was wrapping up her search for a running mate and was considering