Clinton, a Grimes fundraiser and old family friend, is scheduled to stump for her in Louisville on Feb. 25 — the 42nd president’s first campaign appearance of the 2014 cycle.

Paul can be expected to play a key role for McConnell’s campaign during that visit, making the case to voters that Clinton — and Grimes, by association — are fatally flawed. A Tea Party favorite and popular in his state, Paul is perhaps McConnell’s most influential surrogate.

Grimes has adopted the Democratic message that Republicans are engaged in a “war on women” as a central part of her strategy to win over female voters and oust McConnell. Paul’s spotlight on Clinton’s past sexual foibles could undermine that effort.

“Clinton was relatively popular here so we need someone to go and remind people just how terrible of a person he was,” said a Republican operative with Kentucky ties. “Paul has the sort of celebrity status to do that effectively, and I think people are glad he is.”