Romney has said little about whom he favors or when the choice will come, although it's expected well before the Aug. 27 start of the Republican National Convention in Tampa, Fla.
So far, Vice President Joe Biden has had the No. 2 space all to himself, which has given the Obama campaign a second high-level voice to tour the country, raise money and hammer their opposition. Obama's aides deny he has a preference, but admit they're watching closely for Romney's decision.
"Any way you cut it, whomever they pick, we'd much rather have Vice President Biden on our side, campaigning across the country, in the debates, out there standing up for the president, than any of the motley crew that Mitt Romney is choosing between," Obama campaign spokesman Jen Psaki said Wednesday.
Ann Romney, the candidate's wife who just returned from watching her horse compete at the Olympic Games in London, added to the suspense Thursday with an email telling backers "I can't wait" to help introduce "the other half of America's Comeback Team."
Bakst reported from St. Paul, Minn. Associated Press writers Brendan Farrington in Tallahassee, Fla., Mark S. Smith and Melinda Deslatte in Baton Rouge, La., contributed to this report.
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