Democratic Sen. Christopher A. Coons, who handily defeated Ms. O'Donnell three years ago in the contest to fill Vice President Joseph R. Biden's Senate seat, says he hasn't been contacted by congressional investigators or the Treasury Department watchdog responsible for looking into the improper use of Americans' private tax records.
"Any political abuse of the government's power is inappropriate, wrong and ought to be investigated fairly," said Ian Koski, a spokesman for the senator. "This particular matter was already subject to a months-long investigation by the Treasury Department — which found no wrongdoing — and no evidence has been presented that indicates that the Treasury investigation was unfair or inadequate."
The Washington Times first reported last week that Ms. O'Donnell's personal tax records were accessed by a Delaware official, who has now been identified as David Smith, an investigator with the state's Division of Revenue. The breach occurred in March 2010, the same month Ms. O'Donnell announced she would challenge Republican Michael Castle in the party's Senate primary.
The timing and release of information related to Ms. O'Donnell's taxes to the media raises questions about the possible role her political enemies played, and whether Delaware state officials used a backdoor into Americans' confidential IRS tax records.
Delaware officials say a state investigator asked for and received permission to look into Ms. O'Donnell's tax records based on a newspaper report about a lien against her home. It was later revealed that the lien was issued erroneously, and was apparently the result of an IRS computer error.
State officials also say computer files that would show when and how often Ms. O'Donnell's records were accessed likely have been destroyed.
The Treasury Department's inspector general has reopened its investigation of the matter, and Sen. Chuck Grassley, Iowa Republican, is pressing for more information on what safeguards the IRS has in place to stop such snooping.
Ms. O'Donnell said Mr. Coons, who was chief executive in the county in which her former house was located, could play a role in finding answers.
"Since he takes this seriously, will he question his former staff to see who actually filed the lien under his watch?" she said. "Contrary to what he says, there is more he can do. He ran New Castle County when the erroneous lien was filed."
Mr. Coons' camp contends that the New Castle County chief executive would have had no involvement with the IRS lien, which was filed in the county recorder of deeds' office.
"It didn't even fall under the auspices of the county executive," Mr. Koski said.
Meanwhile, Ms. O'Donnell took to Twitter this week to address speculation that she'll mount another Senate campaign in 2014.
"Misinformation is circulating ... To be clear, a 2014 Senate run isn't even on my radar," she wrote.