In recent years, Democrats have largely avoided the contentious primary races that have weakened so many Republican candidates – particularly in races where Tea Party candidates have mounted strong challenges to the “establishment” Republicans. But a powerful new ad on the lively topic of gun control in the Ohio Democratic Senate primary could be a sign Democrats are also building an appetite for viscous primary fights. P.G. Sittenfeld, a 31-year old Cincinnati councilman, entered the Ohio Senate race first, but he has struggled since former Governor Ted Strickland jumped in and quickly wrapped up endorsements from the Ohio Democratic Party and the Democratic Senatorial Campaign Committee. A recent poll showed Sittenfeld tied – with little-known occupational therapist Kelli Prather at just ten percent, compared to Strickland’s 61 percent. The winner will take on incumbent Republican Rob Portman in November in what will be one of the presidential race’s key battleground states. But a new ad from New Leadership for Ohio, a super PAC supporting Sittenfeld, could make waves in the Democratic primary.