Saying that Sen. Norm Coleman may be breaking U.S. Senate ethics rules, DFL Party chair Brian Melendez called on Coleman on Monday to produce his lease and other information on the Capitol Hill apartment he has rented since last summer from a longtime friend and wealthy Republican operative.

Referring to a National Journal article on Coleman's living arrangement that was posted last week, Melendez said he believes Minnesota's senior senator is making below-market monthly payments to rent garden-level living space in a row house owned by St. Paul businessman Jeff Larson.

Larson, whose telemarketing firm has provided services worth more than $1.5 million to Coleman's campaigns and political-action committee since 2001, is the CEO of the local host committee for September's Republican National Convention and was instrumental in bringing the convention to the Twin Cities.

Until April, Larson's wife worked in Coleman's St. Paul office on constituent requests.

At a State Capitol news conference, Melendez said Washington's Capitol Hill-area real estate listings show Coleman is getting a much better deal than other renters would for comparable quarters. DFL officials found similar apartments around the Capitol were fetching rent ranging from $1,100 to $1,450, while Coleman pays $600 a month.

"Senator Coleman is getting a sweetheart deal. He's paying far less than market value and far less than anyone else without his connections would pay. If you're not Norm Coleman, you don't get that kind of deal," Melendez said.

Coleman, a Republican who is being challenged for reelection by DFL candidate Al Franken, was not available for comment Monday. But last week he said he was simply renting "cramped space" from a friend to cut living expenses as his son enters law school and his daughter enters college.

His bedroom isn't quite 10 by 10 feet, he said, and he has a bathroom but no kitchen.

And he acknowledged not only that he had missed two monthly rent payments, but that he paid for another month by giving Larson some of his old furniture for the common area of the lower level, which is used as office space occasionally by a Larson employee. He has since set up an automatic withdrawal system for his rent checks.

"I take responsibility for any negative perceptions, but again, [Larson] is a friend, not a lobbyist," Coleman said. "There are no taxpayer dollars involved, no government contracts. ... No Senate rules have been violated. I have nothing to hide. At this point, I'll continue [to rent there]."

Melendez suggested that discounted rent could be considered a gift to Coleman. Senate rules, while strictly prohibiting gifts of more than $50, grant a bit more leeway for longtime friends and associates. Even then, gifts to senators of $250 or more from friends -- including discounts for lodging -- are prohibited unless first approved by the ethics committee.

Tom Steward, a Coleman spokesman, said the senator had gotten no such approval because he didn't need it.

"As the senator indicated to the National Journal and further articulated last Friday, he is paying fair market value for his cramped bedroom in a basement of a home in D.C. As our research shows, this rent is comparable to other rent in the D.C. area," Steward said.

Although Coleman makes $169,300 a year as a member of Congress, he's far from a wealthy man by Washington standards. Along with a house in St. Paul, his biggest asset is an individual retirement account of more than $500,000 carried over from his time as mayor.

The residence is on North Carolina Avenue S.E., a quiet street lined with classic row houses four blocks south of the Capitol. A Star Tribune reporter knocked on the door Monday, but a woman who answered declined to comment.

According to the National Journal, Larson rents the top floors of the house to a business partner on leave to work for the Republican National Committee.

Melendez said that a 2007 listing for the row house makes the accommodations sound much more comfortable than the "little room in the basement" that Coleman has described.

The three-story row house, which was listed for $989,900, has "a huge English basement with a media center, office space, gorgeous custom marble and oak bar plus an airy guest bedroom and bath," according to the real estate notice.

"This degree of mutual back-scratching ... is not acceptable," Melendez said. "And it's simply not enough for Coleman to say that he's trying to make ends meet by living at the house with an old friend, no matter how much he tries to downplay what he's getting there."

Staff writers Patricia Lopez and Emily Kaiser contributed to this story. Kevin Duchschere • 612-673-4455