Growing pains within Fred Thompson's "non-campaign" for president in 2008 revealed themselves in a big way Tuesday.

For months, the former Tennessee senator has been rising in the polls by merely "testing the waters" and refusing to undertake the traditional trappings of a presidential campaign.

But there has been much speculation about the role of Thompson's wife, Jeri Kehn Thompson, and today, a senior adviser to Fred Thompson today stepped out of a day-to-day role in the campaign because of friction with her.

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When asked to confirm reports that Tom Collamore would reduce his role to senior adviser, two senior Thompson insiders adamantly denied it to FOX News today, insisting that the emergence of Randy Enright as campaign manager and the reduction of Tom Collamore's role had always been part of the plan.

But multiple sources close to Thompson now tell FOX News that denial was inaccurate. In fact, Collamore and Kehn butted heads, and that was partially responsible for Collamore's move.

Thompson's wife Jeri is a hard-nosed former Republican party operative and a long time political professional with a strong will. Insiders have long speculated that her personality would play a big role in the narrative of Thompson's candidacy.

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Carl Cameron currently serves as Fox News Channel's (FNC) Washington-based chief political correspondent. He joined FNC in 1996 as a correspondent.