Broncos general manager John Elway is searching for the next great franchise quarterback. Will that cornerstone arrive in Denver through the draft this spring? The Broncos signed quarterback Case Keenum to a two-year, $36-million contract last year. Elway, in a recent interview with NBC Sports’ Peter King, called Keenum “probably a short-term fix.” Here’s a look at six potential long-term solutions from the college ranks.