If I remember my NY electoral law correctly, a party can’t replace a nominee unless he (i) dies, (ii) moves out of state or (iii) is nominated for state judge. Of course, Grimm hasn’t won the GOP nomination yet, so maybe a write-in can beat him in the primary.
So if worse comes to worse we can nominate him for state judge for some seat in the Bronx we aren't gonna win anyway (didn't someone use that trick to quit?)? This could one instance where the total absurdity of NY having a separate later primary for state offices works in our favor. The new nominee wouldn't have much time before November though.
Another option is run someone as an indie, deadline for them isn't until August.
I'm flashing back to Tom Delay's seat, Sekula-Gibbs as a write in for the GE, ugh.
And Florida, leaving Tom Foley's name on the ballot but letting the votes count for Negron, that was just bizarre.