republican front-runner. phil mattingly is "out front" in new hampshire tonight. >> the political air war kicking into high gear. >> you want someone to read one hell of a bedtime story? ted cruz is your guys. >> reporter: across televisions, the republican primary has gotten tough on the issues. >> politics would be very different if lawyers or bankers were crossing the rio grande. >> reporter: on democrats. >> he's the one hillary doesn't want to run against. >> unlike some, his day is now booming. >> the only one escaping the onslaught? donald trump. >> he's calling for a temporary shutdown on muslims entering the united states. >> reporter: as trump's new ad hit the air waves in iowa, other candidates are hoping these will make, not break, their campaigns. the ad spending millions from the top tier candidates underscore s the urgency of th moment. 36 days until the new hampshire primary. while the other candidates seem