The FBI said Friday that Wyoming officials would take over an investigation into a Colorado gubernatorial candidate's campaign ad to avoid potential conflicts of interest after authorities learned a Denver-area federal agent may have been involved.

The investigation is examining whether GOP Rep. Bob Beauprez accessed a restricted federal database for information used in a television ad to attack his Democratic challenger, Bill Ritter.

Beauprez has denied any wrongdoing and has refused to disclose the name of the person who gave his campaign the information.

"It's important this thing comes to a close quickly. Right now, we have no indication we are even the subject of an inquiry," Beauprez spokesman John Marshall said.

FBI spokeswoman Rene VonderHaar said the U.S. attorney's office in Denver recused itself from the case when it learned of the possible involvement of a Denver-based federal agent. The Department of Justice transferred control of the investigation to its Cheyenne, Wyo., office, she said.

Cory Voorhis, a federal Immigration and Customs Enforcement agent and registered Colorado Republican, provided the information, a person in government who was briefed on the investigation told The Associated Press last week. The person spoke on condition of anonymity because of the investigation.

Voorhis has not publicly commented.

Spokesmen for the U.S. attorneys in both states refused to comment. ICE officials have not returned calls.

The ad suggested Ritter, a former Denver district attorney, was soft on illegal immigration, saying he accepted a plea bargain with an illegal immigrant arrested in Colorado who was later accused of sexually assaulting a child in California. The ad said the plea bargain didn't require deportation.

State investigators, acting on accusations of wrongdoing by Ritter's campaign, concluded the information came from the National Crime Information Center, a federal database that is supposed to be limited to law-enforcement use. The FBI has launched its own investigation.

Using the database for any purpose other than law enforcement is a federal crime punishable by up to a year in prison.