Kathleen Matthews, with her husband, MSNBC host Chris Matthews, reported that she had raised just over $500,000 for her Maryland Democratic primary campaign in the second quarter of this year. (Rebecca D'Angelo/FOR THE WASHINGTON POST)

Kathleen Matthews raised just over $500,000 in her Democratic primary campaign for Maryland’s 8th Congressional District seat, according to finance reports filed Wednesday.

Matthews, a former news anchor and Marriott International executive, reported $501,105 raised and $482,060 in cash on hand for the second quarter of this year, according to reports filed with the Federal Election Commission. She announced her candidacy June 3. State Sen. Jamie Raskin announced July 7 that he had raised $553,000.

The reports represent the opening shots in the race to replace Rep. Chris Van Hollen (D), who is running for the U.S. Senate seat being vacated by Sen. Barbara A. Mikulski (D). Political professionals have estimated that a winning campaign in the 8th — which covers portions of Montgomery, Carroll and Frederick counties, in one of the nation’s most expensive media markets — could cost anywhere from $1 million to $3 million.

Matthews, wife of MSNBC host Chris Matthews, drew from a deep network of friends and supporters in Beltway Democratic circles. Campaign filings list Barbara D. Boggs, widow of powerhouse lobbyist Thomas H. Boggs Jr. and a Chevy Chase neighbor, as treasurer. Lobbyist Heather Podesta recently held a fundraiser at her home featuring prominent LGBT leaders. Contributors included former Senate Democratic leader Thomas A. Daschle and his wife, Linda, as well as former Hillary Rodham Clinton strategist Mark Penn and former Federal Communications Commission chair Reed Hundt. Marriott International Executive Chairman J.W. Marriott Jr. and other company executives also contributed.

Del. Kumar Barve, who was the first announced candidate for the seat in March, said he will report $291,000 (including $66,000 collected in the first quarter of the year) with $229,000 in cash on hand.

Former Obama administration official Will Jawando said his campaign will report $112,000 raised.

Del. Ana Sol-Gutierrez said late Wednesday she was still working on her filing.

Former Montgomery County Council member Valerie Ervin, who announced her candidacy just after the end of the second quarter, did not have to file a report.