>>> recent polls show arizona senator john mccain leading challenger ann kirk kirkpatrick. >> they meet for their only debate tonight before their november 8 election. preview. >> reporter: we are outside a.s.u.'s cronkite school this is where the studios are for pbs and that is where you can watch the debate between ann kirk kirkpatrick. and john mccain. they will be standing up at podiums and the moderator will be sitting at a table asking questions. john mccain made it tough primary and is running for a sixth term. his challenger has been a congresswoman for multiple terms and ran hotly contested races of her own. she has been hammering john mccain for his support of donald trump. after donald trump's videos came out for making controversial comments about weekend, mccain withdrew his support over the the debate at 7:00 tonight. there hasn't been too much polling about the race. mccain has a double-digit lead over kirkpatrick but that poll was conducted before the events of the past weekend. i'm andrew hasbun, fox 10 news. >> it could be an interesting night out there. one of the mos