On the Webcast Extra, with less than 2 weeks to Election Day top campaign surrogates like Hillary Clinton, Sarah Palin and Michelle Obama are hitting the trail. What’s the motivation for these campaign appearances? Some like Sen. Rand Paul, who has a large libertarian following, could be broadening his appeal with Republican voters, says CNBC’s John Harwood. Others like the first lady are campaigning where President Obama’s popularity is sagging. Will these surrogates drive voter enthusiasm?