ST. LOUIS –- Democrats seized on a new poll of battleground states Thursday that indicated the Obama campaign's attacks on Mitt Romney's private equity career may have tarnished the Republican in voter's minds.

A survey by Purple Strategies, a Washington-based bipartisan group of political consultants, of voters in Colorado, Virginia, Ohio and Pennsylvania showed that in three of the four states, more voters believe that private equity "hurts workers" than think it "helps [the] economy."

The numbers provoked cries of vindication from Democrats in and around the Obama campaign, who have seen their criticism of Romney's Bain Capital career undermined in recent weeks by prominent Democrats who have strayed from their talking points or outright disagreed with them.

Democrats unleashed howls of derision on the press for reporting in recent days that the Bain attacks have backfired, a storyline fueled in part by the fact that the Obama campaign has backed off the issue since Memorial Day, refocusing on Romney's time as governor of Massachusetts instead.

"Sorry Acela corridor," wrote Brad Woodhouse, communications director for the Democratic National Committee. "It works."

He included a Los Angeles Times report on the Purple Strategies survey with the headline, "Obama's Bain bashing brings benefits, poll shows." He also included a report from ABC on focus groups in Las Vegas, and Richmond, Va., where female swing voters expressed concern about Romney's actions at Bain.

The Obama campaign has released two commercials about companies that were bought by Bain and then closed plants, costing workers their jobs. Each time they did so on a Monday, first on May 14 and then a week later on May 21.

But they shifted gears to Romney's Massachusetts record last week. Romney has said the Bain attacks are evidence that Obama doesn't understand the DNA of the economy, and by extension America itself.

"That is how this country works: individuals pursuing their own dreams and their own interests can in some cases achieve extraordinary success," Romney said at a fundraiser here with 300 supporters at a Ritz-Carlton hotel Thursday evening. "And their success does not make us poorer. Their success makes us better off. When the president attacks it, he doesn't understand America, and how it works."

Bob Shrum, a veteran Democratic strategist who has run several presidential campaigns, spoke in support of the Obama campaign and the strategy of going after Bain.

"I have no interest in second-guessing people in Chicago, who have very reliable information from a very good pollster, and I think they know what they're doing," Shrum said in an interview.

"The surrogate mess is basically a function of the Acela corridor. Voters in Ohio or Michigan or Pennsylvania, they hear the argument, and now they're hearing an argument about Romney as governor," Shrum said. "I believe it will work. These people aren't crazy you know."

But some veteran Democratic operatives privately told The Huffington Post that they felt the Obama campaign's message has, indeed, been erratic, swerving from one emphasis to another, and undercut by the lack of a positive vision for a second term.

"It would be helpful to have a robust second term agenda that you're campaigning on, something forward-looking, vision oriented, rather than just saying I want to do tax reform," said one Democratic operative.

Time's Mark Halperin reported the same thing, writing that "veteran Democratic strategists from previous presidential bids and on Capitol Hill now wonder if the Obama re-election crew is working with the right message."

Such comments from anonymous Democrats outraged Shrum, who pointed his finger squarely at the political orbit surrounding former President Bill Clinton, who has himself played a central role in the Democratic soap opera with a series of unhelpful comments.

"This whole thing is ridiculous. It is generated by a bunch of people who think they ought to be running the campaign or that someone else should be the candidate. It is a disease in the Democratic party that has hurt us in the past," Shrum said.

During the 2004 campaign, when Shrum was a senior adviser to Sen. John Kerry (D-Mass), he said that Democrats associated with former President Bill Clinton second-guessed the Kerry campaign in a similar way "in late-August and early-September."

"It was not helpful," he said.

Shrum said he did not think Clinton himself was actively trying to sow doubts about Obama's campaign strategy, but he did knock the former president for saying that the Obama campaign should not attack Romney's private equity career.

"The idea that president Clinton would say, 'Well, he ought to run a positive campaign.' What campaign did he run in 1996? It was so relentlessly negative that by the end, we thought [Bob] Dole's name was [Newt] Gingrich," Shrum said.

Jim Manley, a former senior aide to Senate Majority Leader Harry Reid (D-Nev), also dismissed the Obama doubters.

"I have no idea what these so called strategists are talking about. What are they suggesting, that Dems spend less time focusing on Mitt Romney's failed record at Bain? Give me a break," Manley wrote in an e-mail. "I would take whatever Mark Halperin says with a grain of salt, and do the exact opposite."

Romney's campaign leaders said they see the Obama attacks as inept.

"I think it's a mistake on their part. I hope they keep it up. I think they're convinced that the way to defeat Mitt is to define him as a corporate raider, or whatever," a senior Romney campaign adviser said.

"I read this somewhere, that the only way they think they can beat Mitt is to define him before we do. It's true," the Romney adviser said. "Outside of Republican primary states where there's a competitive primary, this time and last time, folks don't really know Mitt. So they're trying to go define him."

"But I think they're discovering that we're better than they realized. The candidate's better off, we're structurally better and we're organizationally better. And we hit back better. And I think they're surprised by that," he added.

The Wall Street Journal's Daniel Henninger captured what many Republicans have been thinking lately about the Obama attacks on Romney in his Thursday column: "It's not sticking."

The Purple Strategies poll gave Democrats hope that it is, in fact, sticking, though there were of course denials that there has been any doubt about the campaign's plan.

In Ohio, 49 percent thought private equity hurt workers, 33 percent thought it helps the economy, and 18 percent were undecided. In Florida, 47 percent thought it hurt workers, 40 percent thought it helps the economy, and 14 percent were undecided. In Colorado, it was close: 44 percent said it hurts workers, 43 percent said it helps the economy, and 13 percent were undecided.

And in Virginia, private equity got more positive reviews than negative: 44 percent said it helps the economy, 42 percent said it hurts workers, and 14 percent were undecided.

When voters were asked who they would rather vote for, Romney was ahead of Obama in Ohio and Florida, by three and four percentage points respectively, and trailed Obama in Colorado and Virginia, by two points and three points, respectively.

Somewhat oddly, Romney had come from five percentage points behind Obama in Ohio in April, down 49 percent to 44 percent before the Bain attacks were launched by the Obama campaign, to being ahead 48 percent to 45 percent.

And in a series of other questions about the two men, Romney had a clear edge with independent voters in a series of key questions: 8 percent more thought Romney has "new ideas to lead us into the future," 12 percent more thought Romney "knows what it takes to create jobs," and 13 percent more said Romney "will change the way Washington does business."