Two of the Club's political arms are TV launching ads in three races today (in addition to TX SEN, spots are also being introduced against GOP Reps. Fred Upton and Tim Murphy). A source familiar with the total buy size in all three states said over $500,000 is being spent in total to air the commercials. It's not immediately clear how much is being spent specifically in Texas, a very expensive state with multiple major markets. But the Club's spot is notable because it marks the first time in the race anyone has gone directly after Dewhurst on TV. For Cruz to catch the frontrunner, he'll need major bucks spent on his behalf from allied groups like the Club. But if the buys are just marginal, that doesn't speak too highly of the confidence Cruz's backers have in his chances.