The probe, conducted by one Republican and one Democratic state prosecutor in Utah, has received accusations from an indicted businessman and political donor, interviewed other witnesses and gathered preliminary evidence such as financial records, Congressional Record statements and photographs that corroborate some aspects of the accusations, officials have told The Washington Times and ABC News.

But the Justice Department’s public integrity section — which normally handles corruption cases involving elected figures — rejected FBI agents’ bid to use a federal grand jury and subpoenas to determine whether the accusations are true and whether any federal crimes were committed by state and federal officials.

The information involving Mr. Reid and Mr. Lee is not fully developed but centers on two primary issues:

• Whether both or either politician sought or received money or other benefits from donors and/or fundraisers in connection with doing political favors or taking official actions.

• Whether Mr. Lee provided accurate information when he bought, then sold a Utah home for a big loss to a campaign contributor and federal contractor, leaving his mortgage bank to absorb large losses.