Iowa's first lady, who had said she would stay neutral in the presidential race, has changed her mind and plans to endorse Democrat John Edwards Monday... Culver said her husband, Gov. Chet Culver, will not endorse anyone, and she said her stance does not imply that he supports Edwards... Mari Culver's predecessor as first lady, Christie Vilsack, endorsed Massachusetts Sen. John Kerry before the 2004 caucuses, which he won... Edwards, who also ran for president that year, said in an interview today that he believes Vilsack's endorsement helped Kerry... Edwards said he hopes Culver's backing will help him the same...