The Social Security Advisory Board’s Democratic chair and a Republican member said Tuesday there is no reason to believe President Obama’s choice to head the Social Security Administration is guilty of mismanagement and covering up cost overruns—allegations that threaten her confirmation.

After originally giving her his support, incoming Senate Finance Committee Chairman Orrin Hatch said he was opposing Acting SSA Commissioner Carolyn Colvin for the permanent post because of concerns about possible contract fraud in the Disability Case Processing System (DCPS).

Following his reversal, Senate Majority Leader Democrat Harry Reid refused to bring Colvin’s nomination to the floor this week, leaving her fate to a Republican-controlled Senate that convenes in January.

Conceived in 2008 as a way to add speed, accuracy and cost savings to disability claims processing by consolidating 54 different state-aided systems into a central computerized operation, the cost of the still-not-operational DCPS has mushroomed from $310 million to $751 million.

Hatch has said he does not want the Senate to vote on Colvin’s nomination until investigations of possible civil and criminal wrongdoing in connection with the system contracts are completed. Lockheed Martin is the central contractor.

Colvin has said she is innocent of any wrongdoing.

Advisory Board Chair Henry Aaron, who said the allegations of wrongdoing are unfounded, praised the Acting Social Security Chief for taking a mess created by her predecessor and bringing DCPS back on track by commissioning an independent review of the system and appointing a sole administrator to oversee the project.

Republican Advisory Board member Lanhee Chen said there is no proof Colvin was incompetent and fraudulent in the handling of DCPS, but he pointed out the investigation is not complete.