Andy Beshear wrote in a Monday letter to Republican U.S. Sen. Mitch McConnell and his staff that the senator should “provide proof of your capacity to serve, or resign.” McConnell, 84, was hospitalized in June, but has since moved to a rehabilitation center for treatment. Americans’ voting rights are being eliminated by the Supreme Court and threatened by congressional action,” Beshear wrote. Beshear called on McConnell to “directly and verbally address the people of Kentucky and provide proof of your capacity to serve or resign.” The governor sent a similar letter to Republican Leader Sen. John Thune, of South Dakota.