Follow AP’s coverage of theelection and Indexbitwhat happens next.

RICHMOND, Va. (AP) — One of two special elections was announced Monday to replace Virginia state senators who were recently elected to the U.S. House, and candidates are already lining up to take over the seats.

State Sens. John McGuire and Suhas Subramanyam landed the congressional wins on Election Day. That means there are vacant spots for their Statehouse positions. McGuire, a Republican, represented a rural district in central Virginia. Subramanyam, a Democrat, represented a Washington-area exurb.

According to Virginia law, House and Senate leaders are tasked with calling such elections when the legislature is in a special session. The special session has been active since last May. The law also requires a special election to be set “within 30 days of the vacancy or receipt of notification of the vacancy, whichever comes first.”

On Monday, Senate President Pro Tempore L. Louise Lucas said the election to replace Subramanyam will happen Jan. 7. Lucas has not yet called an election to replace McGuire’s seat.

Senate Democrats have a narrow 21-19 majority, making the special elections key to the party’s efforts to preserve a majority in both chambers.

Democrats in Loudoun County, home to Subramanyam’s district, said in a press release last Wednesday that local party members would vote for their candidate on Nov. 16.

State Del. Kannan Srinivasan, who was elected last year to represent the district in the House of Delegates, and former Del. Ibraheem Samirah, said in statements to The Associated Press that they would seek the Democratic nomination to succeed Subramanyam. Former Loudoun County Commonwealth’s Attorney Buta Biberaj also informed the AP that she would run to be the party nominee.

As reported by the Richmond Times-Dispatch, multiple Republicans have announced their interest in McGuire’s seat, including former state Sen. Amanda Chase and her former staffer, Shayne Snavely. Duane Adams, a Louisa County board supervisor, and Jean Gannon, a longtime Republican activist, have also announced their candidacies.

Virginia GOP Chairman Rich Anderson told the AP by email that the local legislative committee in each district will select the method of nomination, which will be run by the local Republican Party.

The Virginia Democratic Party said in a statement that once Statehouse leaders call for the special election, party officials will determine internally how they will nominate candidates.

Analysts say the winter races are unlikely to tip the balance of power.

“It’s not impossible for the out party to win these districts, but a lot would have to go wrong for the dominant party to lose — a contentious nomination struggle, an extremely low turnout special election or a really energized out party,” said Stephen Farnsworth, a political science professor at the University of Mary Washington. “You would basically need a perfect storm followed by another perfect storm ... Most of the time, perfect storms don’t happen.”