Propping Up Perriello: In addition to the Florida Senate hijinks, the day's news cycle will focus on Pres. Obama's rally for Rep. Tom Perriello (D-Va.) in Charlottesville in the afternoon. Democrats and Republicans both make compelling arguments about whether this will help or hurt Perriello. Democrats say Perriello's chances rest entirely on turnout and, in particular, high African American turnout. Obama's appearance will undoubtedly help that. Republicans counter by saying that Perriello, by running a strong campaign, already has his base motivated. That, they privately say, is why Perriello is still keeping this race close despite the district's conservative leanings and the national GOP headwind. What Obama will do, Republicans say, is fire up the Republican base and hurt Perriello's chances. Dem Doomsday: The Cook Political Report made 15 House ratings changes late Thursday, and they aren't good news for Democrats. Among them, Rep. Barney Frank's (D-Mass.) district went from Likely Democrat to Lean Democrat, as did Rep. Chellie Pingree's (D-Maine). Rep. Jim Costa (D-Calif.) is now a pure toss up, after almost entirely off the radar screen just a couple weeks ago. And Rep. Walt Minnick (D-Idaho) now finds himself back in the Toss Up column. Democratic Reps. Jim Marshall (Ga.) and Allen Boyd (Fla.) have now moved from Toss Up to Lean Republican. Minnick's Meth Ad: Speaking of Minnick, the National Republican Congressional Committee has gone up with its first ad in the district, and Minnick isn't taking it lightly. The NRCC ad ties Minnick to House Speaker Nancy Pelosi (D-Calif.) and calls on Idaho voters to "put the brakes on Pelosi, replace Walt Minnick." Minnick's campaign is responding by going up with a devastating ad targeting Republican Raul Labrador. The ad features Carlos Lopez, an illegal immigrant, who was arrested for conspiracy to distribute methamphetamine. The ad highlights the U.S. Attorney's office questioning Labrador's ethics, "claiming that he had a specific and pre-existing plan to help Carlos flee to Mexico to avoid the charges." Lopez, according to the ad, was later caught crossing the border again. "Raul Labrador's record on illegal immigration makes him wrong for Idaho," the ad concludes. Wow. NRCC ad: http://bit.ly/aR654K Minnick AD: http://bit.ly/cQDOal White House Watch: Obama heads to Charlottesville for Perriello in the afternoon after he goes to Beltsville, Md., to tour local businesses and deliver remarks on the economy. Vice Pres. Joe Biden heads to Dubuque, Iowa, to rally for Rep. Bruce Braley (D). Daniel Friedman contributed reporting to this post.