On 'This Week': Mayor Antonio Villaraigosa and Gov. Bob McDonnell

NEW YORK, August 24, 2012— -- Virginia Gov. Bob McDonnell, chair of the Republican Platform Committee, and Los Angeles Mayor Antonio Villaraigosa, chair of the Democratic National Convention, face off on the 2012 presidential contest, Sunday on "This Week."

As Republicans gather for their national convention in Tampa next week, Tropical Storm Isaac barrels forward, threatening the coast of Florida. Will the potential hurricane disrupt Mitt Romney's nomination plans? And will the storm over Missouri Senate candidate Rep. Todd Akin's controversial comments on rape remain a distraction for Republicans?

And in the most high-profile speeches of their political careers, can Mitt Romney and Paul Ryan introduce themselves to the American public as a viable alternative to the Obama administration? Can they re-focus the political debate on the economy, and gain a critical bounce in polls as the general election season begins?

Gov. Bob McDonnell and Mayor Antonio Villaraigosa debate the latest in the 2012 election, Sunday on "This Week."

Plus, George Stephanopoulos and the powerhouse roundtable debate all the week's politics, with ABC News' George Will; Rep. Donna Edwards, D-Md.; former Michigan Gov. Jennifer Granholm, host of Current TV's "The War Room"; Republican strategist Mary Matalin; and FOX News anchor Greta Van Susteren.

What do Romney and Ryan need to do in their convention speeches to sell their campaign to a national audience? How should Republican speakers throughout the week challenge President Obama? And will Rep. Akin's rape comments drive away women voters, and threaten Republican chances to re-take the Senate? Plus, will a new book by a Navy SEAL who took part in the raid that killed Osama bin Laden impact the election?

And "This Week" takes its weekly trip through history in "What Year Was It?" See the whole political picture, Sunday on "This Week."