ORLANDO, Fla. – Republican Marco Rubio has a 7-point lead over Democratic challenger Val Demings, according to a poll released Wednesday. The Mason-Dixon Polling & Strategy survey also shows President Joe Biden with a 55% disapproval rating in Florida and 40% approval. U.S. Sen. Rubio had a 49% to 42% advantage over U.S. Rep. Demings, D-Orlando, according to the poll, with 9% undecided. Demings trailed Rubio in every region except heavily Democratic Southeast Florida. Still, said pollster Brad Coker in his analysis, “an incumbent running below 50% often leaves the door open for a challenger to…