More than 75 Republicans have signed a letter urging Republican National Committee Chair Reince Priebus to spend the party's money on helping secure the Republican majority in the Senate, not on Donald Trump's presidential campaign. The letter, whose signers include former congressmen Gordon Humphrey, Mickey Edwards and Christopher Shays; Bruce Bartlett, a member of President George W. Bush's cabinet; and former RNC staff members said that Trump's campaign will have a "catastrophic impact" on down-ballot races.