During September's three GOP debates, Romney pressed Perry on the border-fence opposition and support for education benefits for illegal immigrants who meet certain criteria, neither of which sit well with a segment of primary voters. But Romney has tried as aggressively to undercut Perry's general election allure by attacking his call for ending Social Security, a program millions of older Americans rely upon.
They forced Perry to respond during a series of debates, where Perry's sometimes halting performance raised questions about his staying power as the new GOP frontrunner.
Perry has shown little evidence of changing his early-state strategy, even in New Hampshire where Romney has an edge as a summertime resident and where he campaigned aggressively to a second-place finish in the 2008 leadoff primary.
Perry senior adviser, Dave Carney, said the weekend stops in New Hampshire were not a reaction to criticism that Perry had appeared rattled at times during recent debates.
"We're very pleased with where we are," Carney said. "We're going to continue to do what we've been doing — reaching out to as many voters as possible."
Perry has responded to Romney's criticism with a flurry of jabs aimed at likening Romney to President Barack Obama, the Democrat both men seek to challenge.
Primarily, Perry has criticized Romney for signing a health care measure as governor of Massachusetts in 2006 that requires state residents to be insured, a common pan by Republicans of the federal bill Obama signed last year. But Romney, who gave a speech in Michigan in May addressing Republican doubts about the Massachusetts plan, has largely ignored Perry's attacks.
Perry has also poked at Romney's upper-class background and stoked suspicion about his changes on past positions on social issues, a criticism that dogged him in his 2008 campaign and which he was forced to confront during a New Hampshire appearance this week.
Perry's rough September can be attributed to inexperience on the national stage, compared to the seasoned Romney, top Obama strategist David Axelrod said.
"These campaigns test you every single day. They're hard," Axelrod told The Associated Press in a recent stop in New Hampshire. "For Governor Perry, this is all new."
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