BOISE, Idaho (AP) - The two biggest private prison companies in the nation say they don't want the contract to run a troubled Idaho prison, and that could shrink the pool of potential bidders to just two smaller companies.

GEO Group Inc. sent a letter last month to Josh Tewalt, a deputy chief with the Idaho Department of Correction, notifying the agency that it wouldn't bid on the chance to operate the prison south of Boise when the current $29 million contract, held by Corrections Corporation of America, expires next summer. CCA has also informed the state that it won't bid on the contract.

That leaves two smaller companies in the pool of likely bidders: Centerville, Utah-based Management and Training Corp., and Community Education Centers, based in West Caldwell, N.J.

CEC primarily provides treatment and education programs for inmates at several correctional centers across the country. But it also operates a small number of lock-ups - six jails, each with fewer than 550 inmates, and two prisons, the largest of which has 1,883 beds, according to CEC's website. The company doesn't offer any programs or run any facilities in Idaho but did register lobbyist Jeremy Pisca as its Idaho representative in July.

MTC first came to Idaho in July 2010 when the Correction Department selected it to operate the new Correctional Alternative Placement Program, or CAPP, south of Boise. The CAPP facility only houses inmates who are sentenced under retained jurisdiction programs, and if they successfully complete treatment programs during a short stay at the prison, they have the option of serving the remainder of their sentence on probation. MTC also operates 23 other prison facilities nationwide.

No other correctional management companies had registered lobbyists in Idaho as of Thursday, according to the Idaho secretary of state's office.

In GEO Group's letter, Executive Vice President David Venturella didn't s ay why the Boca Raton, Fla., company decided not to pursue a contract in Idaho.

Correction Department officials declined to talk about whether GEO's decision would influence whether the state moves forward with soliciting bids to run the prison or decides to take over operations itself.

Idaho Board of Correction Chairwoman Robin Sandy and board member David McClusky didn't returned phone messages from The Associated Press. Board member J.R. Van Tassel said he didn't know how the other board members would feel but he plans to ask some "pointed questions" about whether it's wise to continue to use a contractor.

"I'm not the world's biggest fan of privatization," Van Tassel said. "It's working OK with the CAPP facility because that's a select clientele, a cherry picking deal because that's the nature of the program. But I keep saying privatization is a failed experiment. It just hasn't worked."

Brian Finn, the warden of CAPP for MTC, said the company wouldn't make a decision on what to do until the Correction Department issues a formal request for proposals. A spokesman for CEC didn't immediately return a phone message from the AP.

Jennifer Pike with the Idaho Department of Administration, which oversees the bidding process, says the state has the option to not award a contract if there aren't enough bidders.

"There is no minimum threshold for the number of responses that must be received," Pike said in an email.

The Idaho Correctional Center has long been the site of problems for the state. Several inmates and the American Civil Liberties Union have filed federal lawsuits alleging high rates of violence, mismanagement and understaffing. The Correction Department asked Idaho State Police to launch an investigation into possible contract fraud, and CCA has since acknowledged that the department was given falsified staffing reports wrongly showing that thousands of hours of vacant guard posts were staffed.

The investigation is still underway; CCA spokesman Steve Owen has said the Nashville, Tenn., company remains committed to making taxpayers whole for any unverified hours.

Meanwhile, the number of public officials speaking out against keeping the prison privatized is growing. Republican Gov. C.L. "Butch" Otter, a longtime supporter of private prisons, said earlier this year that he was open to considering whether the state should take over the facility. Idaho's Democratic Caucus gave the Board of Correction a letter urging board members to have the department run the facility. Idaho Attorney General Lawrence Wasden said at the Idaho Falls City Club last month that he believes that some government services shouldn't be privatized - including prisons.

The Board of Correction was expected to decide whether to formally start the bidding process at its Nov. 6 meeting, but that meeting was canceled and hasn't been rescheduled.