Updated

Federal investigators are looking into whether California Rep. Jane Harman won backing from a pro-Israel lobbying group in exchange for legislative promises, but so far have found no wrongdoing, sources confirmed to FOX News on Wednesday.

The FBI has been looking into claims since mid-2005 that Harman of California, the top Democrat on the House Permanent Select Committee on Intelligence, made explicit pledges to the American Israel Public Affairs Committee, AIPAC, in exchange for the group's support in her quest to keep her spot on the intelligence panel.

The Washington Post reports one of those pledges was that for AIPAC's help, she would ask Republican administration officials to ease up on a probe of two former AIPAC lobbyists charged with violating the Espionage Act by receiving national defense information and transmitting it to journalists and Israeli Embassy employees. News of the FBI's investigation first appeared Friday in Time magazine.

One source with direct knowledge of the investigation told FOX News: "In order to eventually have some sort of bribery allegation, you have to have a quid pro quo," the legal term for an explicit offer in exchange for something of value. "It isn't clear that she was asking anything from anyone."

The source also expressed suspicion about the timing of the leak because of its proximity to the Nov. 7 election, less than two weeks away. If Democrats win control of Congress, Harman could become the panel's chairwoman.

Sources confirmed that the case is still considered open but no significant activity has taken place recently.

Nevertheless, Harman has hired lawyer Ted Olson to represent her since media began reporting on the investigation. She told Time the allegations of improper conduct would be "irresponsible, laughable and scurrilous." Olson said she had not been contacted by anyone in the Justice Department.

The two AIPAC lobbyists under investigation deny they committed any criminal acts, but have since been fired. Former Defense Department official Lawrence A. Franklin last year pleaded guilty to providing documents to the lobbyists and an Israeli diplomat. He was sentenced to 12 years in prison.

FOX News' Ian McCaleb contributed to this report.