Temple political science professor Christopher Wlezien talked with "Radio Times" about whether or not campaign events — ads, conventions, debates or even the gaffes — impact which candidate will win in November. In his new book The Timeline of Presidential Elections: How Campaigns Do (and Do Not) Matter, Wlezien tracked the course of presidential elections. "What we find with the debates is that there is not much net change in voters' preferences over the course of the debate season," he said.