HARTFORD -- A federal grand jury is looking into consulting work former Gov. John G. Rowland performed for a nursing home company owned by the spouse of Republican 5th Congressional District candidate Lisa Wilson-Foley, her husband confirmed Monday.

Brian Foley told the Associated Press that his firm, Apple Rehab, was asked two months ago to provide documents about the six-month contract Rowland had with the company. The former Republican governor, who resigned from office in 2004 and later served time in federal prison camp on a corruption-related charge, was paid $5,000 a month for his services while he was also a volunteer for Wilson-Foley's campaign.

One of Wilson-Foley's fellow candidates, former FBI agent Mike Clark, filed a federal election complaint over the matter, questioning the financial arrangement and whether the payments should have been reported by the campaign as services benefitting the campaign. Clark has since dropped out of the hotly contested race.

Also Monday, the campaign of Mark Greenberg, another 5th District Republican candidate, confirmed he was contacted as a "factual witness" and has provided the requested information to federal authorities. The campaign also said Greenberg "is not in any way a target of the probe."

The federal investigation, first reported Monday by blogger Kevin Rennie, who also writes a column for the Hartford Courant, comes on the heels of another federal probe involving the 5th District race.

On May 31, federal prosecutors announced they had arrested Robert Braddock, former finance director of House Speaker Chris Donovan, the Democrats' endorsed candidate, charging Braddock with conspiring with others to hide the source of $20,000 in campaign contributions. The money was tied to legislation that would have raised taxes on roll-your-own smoke shop owners. Through his attorney, Braddock has said he has done nothing wrong.

Contacted by email about the investigation into his consulting work, Rowland said, "That's news to me." He later denied being contacted by federal authorities or having received a subpoena.

In April, Wilson-Foley disclosed that Rowland, a longtime family friend, was paid to work as a consultant to her husband's company for six months, ending in March. Brian Foley said in a statement at the time that Rowland consulted on labor relations issues and visited health care facilities, providing feedback on business development initiatives.

Wilson-Foley campaign adviser Chris Healy reiterated on Monday that the arrangement had nothing to do with Rowland's volunteer work on the campaign. Rowland has since stepped down as a volunteer. Healy said the Wilson-Foley campaign has not been contacted by the grand jury or any other federal authorities.

Brian Foley said the documents requested by the grand jury were related to the contract with Rowland. He said he was told not to disclose the request to anyone because the grand jury is operating in secrecy.

Foley said he's "optimistic about the outcome" based on what the grand jury asked for from Apple Rehab, but he did not want to elaborate.

U.S. attorney's office spokesman Tom Carson declined to comment Monday. An FBI spokesman didn't immediately return a message seeking comment.

Wilson-Foley, Greenberg and U.S. Navy veteran Justin Bernier each earned enough support at the recent Republican convention to secure spots in the Aug. 14 primary. They are challenging state Sen. Andrew Roraback, who received the party's endorsement.

On the Democratic side, Donovan is facing a primary challenge from former state Rep. Elizabeth Esty and public affairs representative Daniel Roberti. They are all hoping to fill the seat being vacated by Democratic U.S. Rep. Chris Murphy, who is running for the U.S. Senate.