Jill Biden (left), Sen. Barbara Boxer, California Democrat, and first lady Michelle Obama acknowledge supporters during a fundraiser in Los Angeles on Tuesday. "California, my husband can't do it alone," Mrs. Obama said of the midterm elections Tuesday while appearing with Mrs. Boxer. (Associated Press)

Jill Biden (left), Sen. Barbara Boxer, California Democrat, and first lady Michelle Obama acknowledge supporters during a fundraiser in Los Angeles on Tuesday. "California, my husband can't do it alone," Mrs. Obama said of the midterm elections Tuesday while appearing with Mrs. Boxer. (Associated Press)