U.S. Senate candidates Joe Sestak and Pat Toomey have been exchanging sharp verbal blows as the campaign entered the home stretch. In the past 10 days, the sparring has been relentless, sometimes playing out publicly and in TV ads, at other times via strategically released press releases, social network posts, conference calls and hastily summoned press conferences. "It's very typical and it means that they're close," said Michael Hooper of Temple's Political Science Department. "And it's going to get worse."