An expert on debates says tonight’s showdown between Governor Holden and Claire McCaskill could prove very important in the Democratic gubernatorial primary August third. Central Missouri State University Communications professor and past debate coach, Sam Cox, says few will be surprised by the positions taken by the two candidates tonight, but all will be listening to see how they handle themselves under pressure. Cox says McCaskill must prove to Democrats she can take on the job. Holden, he says, must defend his record while ensuring Democrats his administration can move forward. Cox says it’s unfortunate that perception is more important than answers in debates, but that’s reality. And Cox says the debate tonight is the most important of the two, because it’s the one that gives voters their first impression. He compares it to anybody trying to give a good first impression. Cox says a debate during a party primary offers different challenges than a debate during a general election. He says neither candidate can attack the other’s position too strongly without the risk that they will attack the Democratic Party’s position. Cox coached the Central Missouri State University debate team that won a national championship in the 90s.