Ailing Mitch McConnell is facing a devastating brain damage nightmare as a severe concussion may end the Senate minority leader’s political career after an astounding 38 years in Congress, RadarOnline.com has learned. The Republican bigshot, 81, banged his brain in a terrible March 9 tumble at Washington D.C.’s Waldorf Astoria hotel — nearly four years after another serious fall forced him to have shoulder surgery!