National Journal speculates there could be some big collateral damage for the Republican establishment when, as looks most likely, Rand Paul defeats Trey Grayson in Tuesday’s Kentucky GOP Senate primary:

Kentucky Secretary of State Trey Grayson, who once appeared to have a lock on the GOP Senate nomination, might not be the only Republican from the Bluegrass State whose fortunes take a hit next Tuesday.

If, as polls suggest, Grayson loses the Senate primary to insurgent Rand Paul, some GOP insiders say Senate Minority Leader Mitch McConnell, R-Ky., could find a new bull’s-eye on his back.

South Carolina Sen. Jim DeMint may be angling for McConnell’s job. DeMint has endorsed Paul; McConnell is backing Grayson. National Journal‘s John Mercurio notes,

Armed with DeMint’s endorsement, Paul has stepped up his public assaults on McConnell. This week, for example, he declined to commit his support to McConnell should he be elected. “We’d have to know who the opponent was, and we’d discuss it at that time,” Paul said Monday during a televised debate. Turning his sights on Grayson, he added, “Kentucky wants two U.S. senators, not one. I don’t think we want a rubber stamp of one ‘R’ senator for the other ‘R’ senator.”

Of course, DeMint’s endorsement of a competing “tea party” candidate in the Indiana Senate primary last week was crucial to Dan Coats beating John Hostettler, so whether there’s really such a difference between DeMint and McConnell is an open question.