4) The ad war in the Senate race is really starting to heat up in Indiana, where Treasurer Richard Mourdock has launched his first TV ad (the spot hits Sen. Richard Lugar), a 30-second spot that is airing on statewide cable during the GOP presidential debates. It's a small buy -- just $4,000 -- while Lugar is going up with a new ad of his own. 3) Today is a major marker in the recall effort against Wisconsin GOP Gov. Scott Walker, as organizers will turn in petition signatures in an effort to trigger a recall election. The bottom line is United Wisconsin -- the group spearheading the effort -- is almost certain to have more than enough signatures needed. What's next is a 60-day signature verification period as the state reviews the submissions. Expect speculation over potential Democratic challengers to Walker to kick up a notch in the coming weeks. Former Rep. and current Milwaukee Mayor Tom Barrett, former Dane County Executive Kathleen Falk, state Sen. Jon Erpenbach and even outgoing Sen. Herb Kohl are the names being tossed around as potential Walker challengers. 2) After exiting the presidential race, Jon Huntsman endorsed Mitt Romney, but don't lose sight of the uneasy relationship between the two sides in the lead-up to the alliance. 1) Take a look at the major national headlines following Monday night's debate in South Carolina debate and you'll see a consistent theme: Romney was able to mostly withstand the barbs launched in his direction. The NYT says he "withstood forceful attacks," Ron Brownstein writes that the other GOP candidates blew a chance to stop Romney, while Josh Kraushaar writes that Romney solidified his standing. The Columbia State story says Romney "kept his cool."