(Reuters) - An pro-Democratic redistricting group headed by former U.S. Attorney General Eric Holder sued Wisconsin’s Republican governor, Scott Walker, on Monday for declining to hold special elections for two vacant seats in the state legislature.

FILE PHOTO: Wisconsin Governor Scott Walker speaks during the Conservative Political Action Conference (CPAC) in National Harbor, Maryland, U.S., February 23, 2017. REUTERS/Joshua Roberts

The National Democratic Redistricting Committee alleged in the lawsuit filed in Dane County Circuit Court that Walker was violating the law and denying Wisconsin voters representation by leaving the elected offices unfilled until 2019.

The seats, one in the state Assembly and the other in the state Senate, became vacant in December when two Republican lawmakers resigned to accept jobs in Walker’s administration.

Democrats quickly called for special elections, hoping to pick up seats, but Walker demurred. Last month, a Democrat won a special election for another Wisconsin state Senate seat that Republicans had held for 17 years. Republicans control both state legislative chambers.

“Governor Scott Walker’s refusal to hold special elections is an affront to representative democracy,” Holder, who served as attorney general under former Democratic President Barack Obama, said in a statement issued with the lawsuit.

“Forcing citizens to go more than a year without representation in the state legislature is a plain violation of their rights and we’re hopeful the court will act quickly to order the governor to hold elections,” Holder said.

Representatives for Walker, a Republican first elected in 2010 who has been a leading antagonist of Democrats on labor law and other hot-button issues, could not be reached for comment on Monday afternoon.

A spokeswoman for Walker, Amy Hasenberg, told the Milwaukee Journal Sentinel that his decision to wait to fill the seats was consistent with the law, more practical and a way to save money.

“This D.C.-based special interest group wants to force Wisconsin taxpayers to waste money,” Hasenberg told the newspaper. “The Legislature will be adjourned for 2018 before these seats could be filled in special elections, and staff in these offices are working for constituents until new leaders are elected.”

The National Democratic Redistricting Committee, which bills itself as an anti-gerrymandering group, seeks to position Democrats favorably for the round of redistricting following the 2020 census, according to the election information website Ballotpedia.