I think in KY, the party of the leaving member sends three names of people the gov can pick from. If he (they/she/attack helicopter) declines to pick one of the three, not sure what happens then.McConnell will hang in there as long as he possibly can since the Kentucky governor is a Democrat and will most likely appoint a Democrat replacement.
No idea why Feinstein doesn't step down since in CA a Black Plague Rat could get elected as long as it had a D next to it on the ballot.
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