Washington (CNN) - Sen. John McCain on Sunday joined a cast of former presidential candidates and high-ranking Republicans to weigh in on Florida's August GOP senatorial primary between Florida Gov. Charlie Crist and former Florida House Speaker Marco Rubio.
"I hope that Charlie Crist will remain a Republican," McCain said.
Crist has remained vehement that he would not bow out of the Republican primary race and run as an Independent, despite trailing Rubio by as many as 23 points in a recent Quinnipiac University poll. Crist has until April 30 to decide which party's nomination he will seek.
Crist threw his support to McCain in Florida's 2008 presidential primary. McCain won the primary and Rudy Giuliani dropped out of the presidential race the next day.
McCain's comments come days after Mitt Romney announced his support for Rubio. On State of the Union with Candy Crowley this morning, Senate Minority Leader Mitch McConnell said that Crist would "lose all Republican support if he were to run as an independent."