WASHINGTON — A national real estate group placed a six-figure down payment on Rep. Chris Van Hollen's campaign for U.S. Senate this week, marking the first time an outside group has poured money into the Montgomery County Democrat's run.

The National Association of Realtors spent $554,850 on television and online advertising and a poll, according to a disclosure filed with the Federal Election Commission. Federal Communications Commission reports show that the group's super PAC has purchased broadcast airtime in Baltimore.

Van Hollen's leading opponent in the Democratic primary race for retiring Sen. Barbara A. Mikulski's seat, Rep. Donna F. Edwards, has benefited from an outside group tied to Emily's List, the organization that supports Democratic women candidates.

That group has committed to spend $2.4 million on Edwards' behalf.

Though not a major investment, spending by the real estate group is significant enough to raise a question about whether other outside money will flow into Maryland during this campaign. “NAR makes targeted investments in campaigns at the request of local and state associations who help identify candidates, like Congressman Chris Van Hollen, who have a strong track record of support for homeownership,” Jon Boughtin, the group's spokesman, said in a statement.

The investment will benefit Van Hollen despite the fact that he vociferously argued against outside spending in the race last July. At the time, Van Hollen called on Edwards, of Prince George's County, to sign a pledge that required campaigns to donate 50 percent of any money spent by an outside group.

The pledge Van Hollen proposed was intended to send a signal to super PACs that their investment would have a perverse effect, forcing candidates to relinquish cash each time they engaged.

Edwards declined to sign.

Asked if the Van Hollen campaign would honor the pledge anyway, a spokeswoman declined to answer directly, instead saying in a statement that Van Hollen “is the only one in this race who has taken a stand against outside super PAC money flooding into Maryland” and that “he proposed an Elizabeth Warren-style anti-super PAC pledge to keep them out of this election — the offer was quickly rejected because Congresswoman Edwards has a habit of saying one thing and doing another.”

The 30-second television ad paid for by the association says Van Hollen worked to expand affordable housing and protect the mortgage interest deduction. “Maryland needs and deserves proven, effective leadership,” the narrator says.

john.fritze@baltsun.com

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