The top three Republican candidates running to replace longtime U.S. Sen. Mitch McConnell took the stage Monday night at the Henry Clay event center in downtown Louisville for the first Republican primary debate. McConnell, a Republican who has represented Kentucky in the U.S. Senate since 1985, announced earlier this year that he won’t seek reelection in 2026 after more than 40 years in office, creating the first open Senate seat in the state i…