MADISON, WI (WTAQ) - Four Republicans running in recall elections against Democratic state senators have until Monday to answer challenges to their nomination papers.

Marinette Representative John Nygren and "Recall Hansen" organizer David Vander Leest are two of the candidates who have to answer the challenges. They're looking to face Green Bay Senator Dave Hansen.

The Government Accountability Board says those candidates have to address questions like whether voters who signed their nomination papers actually live in the correct district.

Responses are due by 8 a.m. Monday. At that time the board will meet to consider the challenges and approve the final list of candidates for the elections.

The remaining 2 GOP candidates involved are opposing Senator Jim Holperin.