Appleton, Wisconsin (CNN) – After a relatively quiet week, Mitt Romney shifted sharply into general election mode with a retooled speech Friday.
The GOP candidate – surrounded by an array of American flags arcing widely behind him onstage – assailed President Obama for moving Americans toward "a government-centered society" and called his economic strategy "a bust."
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"President Obama did not cause the recession but he most certainly failed to lead the recovery," Romney charged, ignoring his Republican opponents and instead setting up a clash between himself and the president in advance of the general election campaign to come.
Romney did not delve into policy specifics in his speech, which he read from teleprompters on the Lawrence University auditorium stage.
At several points he seemed to concede the economy had begun to recover, but charged the president had slowed that process – in an apparent effort to forestall the chance an improving economy could undercut his message.
"All in all, President Obama prolonged the recession and slowed the recovery," Romney said. "These troubling facts are President Obama's legacy and now our shared history and as much as we'd like to, we can't undo what's happened these past three years."
A spokesman for Obama's reelection campaign said the economic policies Romney had followed in Massachusetts "mirror those that created the economic crisis in the first place" and accused the Republican of mischaracterizing Obama's record.
"Mitt Romney's latest attempt to pivot to the general election offered little in the way of new solutions and more of the misleading rhetoric that has become par for the course for him," said spokeswoman Lis Smith. "Whether he is willfully ignoring the facts or rooting for failure, Mitt Romney's speech overlooked key facts about the economic progress we've made under President Obama's leadership."
Romney's appearance in Appleton was also notable for its enhanced security measures, as the Secret Service agents protecting the former governor stepped up security checks on the media and the general public attending the event.
A spokesman for the Secret Service would not comment on the changes.
Romney closed his address by returning to his general election theme, asking the Wisconsin audience to support him in that state's primary: "Join me, walk together this Tuesday, and take another step until Nov. 6," he said.
A poll showed Romney had reason for self-confidence in advance of the Badger State's Tuesday vote, where he is leading the GOP field. The former Massachusetts governor is also expected to perform well in the Republican contests in late April, which could help fuel his nomination push.
The White House hopeful was introduced by his newest high-profile supporter: Wisconsin Rep. Paul Ryan, a party up-and-comer and the author of the House Republicans' budget plan.
Ryan seemed to head off concerns by some that Romney has failed to fire up the Republican base.
"I'm excited," he said of Romney. "I'm encouraged. I'm enthused."
Though Romney did not mention his rivals, his campaign did obliquely poke at them by playing Kenny Rogers' song "The Gambler" before the event began. The song - which features the line "know when to fold 'em," was quoted by former President George H. W. Bush Thursday as he urged Republicans to coalesce around Romney.