SACRAMENTO (AP) — The state of California has agreed to mail voter registration forms to nearly 4 million people who have signed up for insurance through its health care exchange after a threat of a lawsuit, the American Civil Liberties Union said Monday. The ACLU of California and others said they threatened to sue the state for failure to comply with the National Voter Registration Act, also called the Motor Voter Act. The law is designed to make it easier for voters to register by requiring there to be opportunities to apply at offices that provide public services.