A pair of U.S. House races in the Maryland suburbs of Washington, D.C., have become some of the most expensive congressional primaries in American history. The flood of cash has prompted candidates to question whether unlimited spending can actually hurt a favored contender.

Voters are beginning to notice the frequency of political ads, according to Prince George's County Council member Wala Blegay, a candidate in Maryland's 5th district. Former Capitol Police officer Harry Dunn, also running in that race, questioned the motives behind such large donations.

Outside groups — including the pro-crypto super PAC Protect Progress and AIPAC's United Democracy Project — had collectively spent $12.5 million in MD-05 as of Monday, according to Federal Election Commission filings. All Democratic candidates in the primary together spent $10.5 million as of June 3.

More than 20 Democrats are vying to succeed former House Majority Leader Steny Hoyer in the district. The primary race has drawn national attention due to the unprecedented spending levels and the crowded field.

Critics argue that such heavy outside spending can distort local elections and drown out grassroots voices. The final impact on voter turnout and candidate viability remains uncertain as primary day approaches.