Christie is not the first Republican to push back on calls to drop out of the race. His first major ad blitz, which started airing in Iowa, New Hampshire and South Carolina, takes aim at Donald Trump for his “no-nothing political stunts.” The ad emphasizes his record as New Jersey governor, saying he’s the only candidate with executive experience who can solve the nation’s problems. Christie also emphasizes his work on entitlement reform and his record of governing “in the spirit of the people” rather than his own ambitions. Christie hopes his ad blitz will help to differentiate him from the other candidates as he fights for an upper-tier finish in the first three primary states.