CHILLICOTHE, OHIO - Closing out his four-day bus tour, Mitt Romney stood on the steps of the courthouse here and ripped apart President Obama's campaign strategy as one of the "diversions" that have taken the nation's highest office to a "new low" that appears "angry and desperate."

"You don't hear any answers coming from President Obama's re-election campaign," said Romney, speaking at his third and final event in Ohio, the last stop on his bus tour that weaved in and out of four battleground states, dramatically opening with the announcement of his running mate, Rep. Paul Ryan.

"That's because he's intellectually exhausted, out of ideas, and out of energy," said Romney of Obama in what was one of his most strongly worded speeches to date. "And so his campaign has resorted to diversions and distractions, to demagoguing and defaming others. It's an old game in politics; what's different this year is that the president is taking things to a new low."

The Obama campaign shot back at Romney's speech, saying that the presumptive GOP nominee seemed "unhinged."

"Governor Romney's comments tonight seemed unhinged, and particularly strange coming at a time when he's pouring tens of millions of dollars into negative ads that are demonstrably false," said Obama spokesman Ben LaBolt.

There have been several attacks lodged against Romney in recent weeks by the Obama campaign and groups that support it. Romney has been accused of being a felon and dodging taxes; it's been implied that he had a role in a woman's death in a pro-Obama SuperPAC ad. Just today, Vice President Joe Biden suggested that Republicans were trying to put Americans "back in chains" with their budget proposals.

But today Romney released a new television ad that accused Obama of stripping funds from Medicare, which followed one earlier this week that accused Obama of removing the work requirements from welfare reform. The welfare ad has been criticized for being over the top, as Obama's proposal does not call for dropping all work requirements and instead allows for states to ask for a waiver for more flexibility in how citizens can earn welfare checks.

Romney drew on quotes from the president's 2008 election, recalling that Obama said that those who don't have fresh ideas "use stale tactics," and that when you have no record to run on, you "paint your opponent as someone people should run from."

"That was Candidate Obama describing the strategy that is now the heart of his campaign," said Romney tonight, as the crowd of thousands erupted into applause. "His campaign and his surrogates have made wild and reckless accusations that disgrace the office of the presidency."

"This is what an angry and desperate presidency looks like," said Romney.

Romney continued his criticism of Obama, who he says has divided America while in office, accusing the president of demonizing some and pandering to others.

"His campaign strategy is to smash America apart," said Romney. "If an American president wins that way, we all lose. But he won't win that way."

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