U.S. Senate candidate Marco Rubio (R-FL) looks on at a public event to sign election documents to officially qualify as a Republican candidate for the U.S. Senate in West Miami, Florida

 
U.S. Senate candidate Marco Rubio (R-FL) looks on at a public event to sign election documents to officially qualify as a Republican candidate for the U.S. Senate in West Miami, Florida
U.S. Senate candidate Marco Rubio (R-FL) looks on at a public event to sign election documents to officially qualify as a Republican party candidate for the U.S. Senate in West Miami, Florida April 27, 2010. Former U.S. Vice President Dick Cheney endorsed Republican Marco Rubio in Florida's U.S. Senate race and coupled his announcement with sharp criticism of Rubio's competitor, Governor Charlie Crist. As conservative favorite Rubio picks up momentum before the August 31 primary, support for Crist has been dropping in the Republican Party to the extent that the Florida governor has been contemplating whether to run as an independent. REUTERS/Carlos Barria (UNITED STATES - Tags: POLITICS)