The president's campaign started swinging at the potential Republican running mates this week while urging home-state Democrats to chime in about the shortcomings that - as emails to donors and supporters put it - "Americans need to know."
The pre-emptive strikes are an effort to define a possible No. 2 in a negative light and reflect a sense that time is precious to sway opinion in a stubbornly close presidential race dashing quickly toward November.
Tim Pawlenty? The former Minnesota governor is a fee-raiser whose record "is painful for the middle-class families who lived under his leadership," the Obama campaign argues.
Rob Portman? The Ohio senator is "one of the architects of the top-down Bush budget" that the Obama team blames for "crashing our economy."
Marco Rubio? The rookie Florida senator has "led the way on almost every extreme position Mitt Romney has embraced," according to the missive that seeks examples of "the good, the bad and ugly" of Rubio.
Chris Christie? There's "no lack of material to work with" about the pugnacious New Jersey governor.
Those views are far from how Republicans regard the foursome. As many in the GOP see it, Pawlenty is extolled for his blue-collar appeal and budget restraints during eight years as governor; Portman is praised for a vast portfolio of experience and as someone who could help deliver a critical swing state; Rubio is a rising star who could help the GOP attract Hispanic voters; and Christie is willing to take on entrenched interests and big problems no matter whom he offends.
Romney's campaign criticized Obama for seeking the critiques. They are little more than "negative smear campaigns against the possible GOP vice presidential nominees," Ohio-based spokesman Chris Maloney said.
It's not just the Obama operation that's trying to tar the Republicans. Local Democratic officials in contested states aren't letting visits by the would-be vice presidents go unchecked.
In conference calls, they try to draw attention to what they say are the Republicans' flaws, then quickly deliver biting assessments when one of them campaigns in a battleground state. Independent groups sympathetic to Obama are piling on as well.
American Bridge 21st Century, a Washington-based super PAC, has already dumped a combined 1,651 unflattering pages of so-called opposition research on Pawlenty, Portman and Rubio as well as Louisiana Gov. Bobby Jindal and Wisconsin Rep. Paul Ryan.
The five electronic briefing books, including two released Wednesday, rake over the Republicans' voting records, proposals, public statements and slipups. The rundowns are so detailed that a politician's taste for expensive wine is even noted in one of the books.
American Bridge President Rodell Mollineau said the group started months ago compiling the information - much of it's drawn from media reports, public records and speeches - and decided against waiting until the vice presidential pick becomes known to trickle out the juiciest bits.
"You don't want to start too soon, but you don't want to be in a situation where there's 80 days until the election and everything is being jammed in so much that things are being lost," Mollineau said.
The findings are likely to buttress criticism from top Democrats, feed into TV ads and show up as part of fall campaign mailings. The group also has video trackers in key areas eager to capture possible miscues or shifting positions.
The Obama campaign dispatches haven't gone unnoticed on the right.
Natalie Baur, a confidante of Portman, went so far as to issue a rebuttal to fellow supporters defending Portman as a problem-solver. The message called the Obama push for feedback on him a "desperate" move and a sign that "the president's friends are more interested in playing political games than working together to create jobs, fix the economy and pass a budget."
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., and Mark S. Smith in Washington contributed to this report.