"They haven't worked," GOP strategist Charlie Black, an informal Romney adviser, said of the Bain criticisms. "People are worried about the economy and jobs."
Democratic strategist Steve Elmendorf said too few voters had heard the argument.
"The reality is it's June," said Elmendorf. "To say the Bain argument has worked or not is ridiculously premature."
A handful of swing-voting states will be the most hard fought as Obama and Romney aggressively build get-out-the-vote organizations and air a flood of advertisements in their efforts to reach the 270 Electoral College votes needed to win the White House.
Across the country, Romney's campaign is going through growing pains as it seeks to turn a stripped-down primary operation into a full-scale general election campaign. Aides say offices will open and more staff will join the team, but they also say they don't anticipate being able to match the staffing levels of Obama, who has had teams in place for months in states like Florida and Ohio. The Republican National Committee also is in the midst of boosting its staffing to help Romney.
Already, Obama's and Romney's campaigns, as well as super PACs supporting and opposing each, have spent more than $80 million in advertising on the general election campaign through the month of June, according to ad-tracking reports provided to The Associated Press by Smart Media Group of Alexandria, Va.
Of that, Obama's campaign has spent $31 million-plus on TV ads in about 10 states. He's been on the air most heavily in Florida, Iowa, Ohio and Virginia, an indication of where his team may think the race will be won or lost. A Democratic-leaning super PAC also has been on the air to help him, though it's spent only about $6.3 million.
Romney himself has run ads in just five battleground states: Iowa, New Hampshire, North Carolina, Ohio and Virginia. But he's been significantly helped by pro-Romney outside groups, who have been on the air in several others — most heavily in Florida, Ohio and Virginia.
Even so, Republican outfits, including Romney's campaign and supporting super PACS, have combined to spend about as much as Obama and his allies. And in the coming weeks, Romney plans to focus heavily on fundraising so that he'll be able to make strategic decisions about where to devote most of it state by state.
To that end, Romney is spending the week courting donors in California, starting Wednesday in Fresno, Bakersfield and in Hillsborough, a wealthy enclave just outside San Francisco.
He planned major fundraising events Thursday, Friday and Saturday in southern California. On Tuesday, Romney was in Las Vegas wooing Sheldon Adelson, the primary financing source of a group that backed Newt Gingrich's failed primary campaign. And Romney also attended a fundraiser hosted by Donald Trump.
Associated Press writers Kasie Hunt and Steve Peoples in California, Beth Fouhy in New York and Anne Gearan in Washington contributed to this report.
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