Texas Gov. Rick Perry’s campaign is moving aggressively to reassure key Republican leaders, donors and activists of his strength as a candidate, after a series of uneven performances this month.

Perry held a telephone town hall on Monday night with thousands of activists from the early voting states of Iowa and New Hampshire, where he detailed and defended his immigration views, trying to mend fences with conservatives who grew alarmed last week after he accused those who disagree with him of being heartless.

Top campaign strategists have scheduled a conference call with leading donors on Wednesday afternoon, and Perry stepped up his attacks this week on his chief rival, former Massachusetts governor Mitt Romney, by releasing two tough videos accusing Romney of shifting positions.

The campaign has denied the debates were a major problem. “This is a long campaign,” campaign spokesman Mark Miner said. “It’s a long road, and the governor is going to continue doing what he’s doing — travel the country, talk about issues that matter to the voters. This campaign is about the failed leadership of President Obama.”

In the telephone town hall, which was first reported by CNN, Perry emphasized he would support a fence along some parts of the U.S. border with Mexico. Some party activists are frustrated that Perry does not support a border-wide fence.

He defended his decision to allow some illegal immigrants to pay reduced, in-state tuition to Texas universities but said it was “a Texas solution for a Texas problem” and he would not impose such a policy nationally.

In the call, according to a Republican who listened to it, Perry did not specifically address his debate performances. Nor did he attack his opponents.

But Perry has all but conceded that he has not been effective on stage with his rivals, saying at recent campaign stops that the party should pick the best candidate, not the “smoothest debater.”

“Yep, there may be slicker candidates and there may be smoother debaters, but I know what I believe in,” Perry said Saturday on Mackinac Island, Mich. “And I’m gonna stand on that belief every day. I will guide this country with a deep, deep rudder.”

His performances, in which he has at times struggled to answer questions or speak clearly in full sentences, have energized his rivals. Increasingly, they are questioning not only Perry’s views but also his knowledge and intelligence.

Two of his opponents — Romney and former senator Rick Santorum of Pennsylvania — have made thinly veiled comments over the past two weeks suggesting that Perry did not write books or speeches that bear his name.

Some of Perry’s supporters are equally blunt, although they largely shy away from bashing him publicly.

“He’s going to have to study,” said one major Perry benefactor, who requested anonymity to offer a criticism of the candidate. “I don’t think he’s taking it as seriously as he should.”

William Diamond, a Perry donor from Florida, said, “He has to be more succinct.”

Perry aides would not discuss how he has prepared for three earlier debates or whether he has a formal debate coach.

Unlike some other candidates, Perry has not identified who is advising him on major issues other than Deirdre Delisi, a longtime Texas aide who is serving as the campaign’s policy director.

Perry’s supporters emphasize that other candidates, in particular Romney, have been running for president far longer than the Texas governor. And they argue that the winner of the campaign won’t just be the best debater.

David Wilkins, a former ambassador in the Bush administration who is one of Perry’s most prominent backers in South Carolina, said Perry’s support there remains “very broad and strong.” He said a substantial number of state legislators have decided to back Perry in recent days and “more are coming.”

“Obviously debates are an important part of the process,” Wilkins said. “But so is your individual message and so is your ability to work the crowd and so is your record. I think all of that has to be considered together. I haven’t felt or noticed any diminishing of his support in South Carolina the last couple of weeks.”

Staff writer Amy Gardner contributed to this report.

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