Republican U.S. Senate candidate Lt. Gov. David Dewhurst makes a campaign stop, Saturday, July 28, 2012, in Amarillo, Texas. U.S. Senate hopefuls Dewhurst and Ted Cruz are crisscrossing the state three days before a runoff election for the Republican nomination. (Associated Press)

Republican U.S. Senate candidate Lt. Gov. David Dewhurst makes a campaign stop, Saturday, July 28, 2012, in Amarillo, Texas. U.S. Senate hopefuls Dewhurst and Ted Cruz are crisscrossing the state three days before a runoff election for the Republican nomination. (Associated Press)