The campaign manager for Republican presidential candidate Jon M. Huntsman Jr. left that job Thursday, the clearest sign that the campaign, which began with considerable hype a month ago, is having trouble gaining traction.

In a significant staffing shake-up, Susie Wiles stepped down from the top post, saying that she had always intended to get the former Utah governor’s campaign off the ground and then move on. She will be replaced by Matt David, a communications aide who worked on the presidential campaign of Sen. John McCain (R-Ariz.) in 2008 and who is closer to the campaign’s core group of former McCain aides, including lead adviser John Weaver.

The move comes weeks after Wiles oversaw Huntsman’s campaign rollout, which was riddled with errors, from a misspelling of the candidate’s name to an announcement speech that was staged poorly for television.

Huntsman aides, who are scheduled to meet in Washington on Friday for a strategy session, said Wiles’s departure signals the start of a second phase of the campaign. They acknowledge that the presidential bid has gotten off to a rocky start and must soon see some movement in the polls.

“Now the campaign is moving into phase two, which will be more aggressive from a messaging and tactical standpoint, and Matt is prepared to take that on,” Weaver said.

High-level staff departures early in a presidential campaign are generally seen as a bad thing, but Wiles is the only known departure from Huntsman’s team. (Another staffer recently took a leave for personal reasons.)

Wiles came to the Huntsman effort after leading health-care executive Rick Scott (R) to victory in the Florida governor’s race in 2010. She joined a political action committee devoted to Huntsman’s impending campaign in January and became campaign manager of the fledgling effort last month.

In an interview with the Miami Herald, Wiles said it was “just time” for her to move on.

“I signed up to get it started,” she said. “It’s like a phase. This morning I said it’s time to move on.”

Wiles’s husband, veteran advanceman Lanny Wiles, also works for Huntsman and will remain with the campaign, according to staff.

Huntsman, who officially entered the presidential race about a month ago, has yet to catch on in the polls, but has assembled a team of well-regarded political minds, many who guided McCain’s 2008 campaign.

David is a veteran of former California governor Arnold Schwarzenegger’s (R) team, where he served as his top communications aide. Previously, he was deputy communications director for McCain in 2008 and was part of Schwarzenegger’s successful 2006 reelection campaign, as well as a communications aide to President Bush’s 2004 reelection campaign.

Huntsman, who most recently served as President Obama’s ambassador to China, has proved to be a top fundraiser in what has generally been a weak GOP fundraising field, pulling in more than $4 million in the final days of June, according to his campaign. That total included $2 million of his own money.

Huntsman’s campaign has been criticized for not having a defined message, and many think he will struggle with his moderate record and ties to Obama.

Aides say that will begin to change in the days ahead, as Huntsman returns for a long stay in New Hampshire — a key state — and delivers several speeches.

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