By Cameron Joseph - 07/27/12 03:21 PM EDT
This race will be won or lost by whether Donnelly can get enough separation from Obama and his party to win over independents and centrist Republicans unhappy with Mourdock for defeating Sen. Dick Lugar (R-Ind.) in the primary, or whether Mourdock can get distance from his previous hard-right statements and positions and turn the race into a choice between an acceptable Republican and a standard Democrat.
Donnelly has already been on the air pushing some of Mourdock's more conservative views.
The ad has $100,000 behind it, a substantial buy in the state, and notably is running in Indianapolis and South Bend, Lugar's and Donnelly's bases, and not in Evansville, where Mourdock hails from.