Bill Richardson, a Democrat and governor of New Mexico, is dropping his bid for the presidency, the Associated Press is reporting.

The news service said Mr. Richardson plans to make an official announcement later today. The governor placed fourth among the Democratic candidates in both Iowa and New Hampshire.

During his campaign, Mr. Richardson pitched a wide-ranging agenda for education, offering a plan in October that included proposals to broaden the federal national-service program, train more math and science teachers, provide incentives for colleges to rein in tuition, and increase funds for vocational-education programs.

On immigration, which has been hotly debated during the campaign, Mr. Richardson has a record of supporting public benefits for some illegal immigrants. As governor, he signed laws that allow some illegal immigrants to pay in-state tuition and also receive aid under the state’s lottery-financed college-scholarship program.