later tweeting this video on the plane with senator tim scott and governor nikki haley. >> it's going to be a great night in south carolina. >> reporter: do you feel a lot of pressure? >> it's in god's hands tomorrow. work we've put in. >> if we work together, we win. >> reporter: but tonight, cruz with some problems of his own. new lawsuits in at least six states challenging whether cruz's name can appear on the ballot because he was born in canada. >> all of this on the eve on south carolina. tom llamas live from that state. how is cruz responding to the lawsuits? >> the cruz campaign says it's no coincidence. that all the lawsuits are being filed around the time of the primary. they have lawyers fighting back, saying he is an american because his mother was an american when he was born. >>> and in nevada, the neck and neck battle between bernie sanders and hillary clinton. the latest poll showing a dead heat. and the national poll, clinton hillary clinton getting a gift, an early endorsement. that could be crucial in south carolina. and bernie sanders confident, saying he was once

haley and senator tim scott with rubio. senator lindsey graham in jeb bush's camp. today, trashing the billionaire. >> i think he's crazy. i think he's unfit for office. >> reporter: trump says graham's >> the guy is a nut job. little thimble. this guy -- let me tell you, this guy knows nothing. taking on senator ted cruz, the candidate who could be his toughest competition. >> and for the first time in many months, there's a new national front-runner on the republican side. >> reporter: trump's lawyers and desist letter over this ad. >> i am pro choice in every respect. >> we cannot trust donald trump. >> reporter: trump claiming the ad is "replete with outright lies, false, defamatory and destructive statements." >> in the annals of frivolous lawsuits, this takes the cake. >> reporter: but cruz, a battle-tested lawyer, says he's ready. >> one of the things i look forward to most of all is deposing donald trump. i make take the deposition myself. >> and tom llamas back with us live. %-ptom, i wanttoget backtothat key endorsement moments ago from governor nikki hale