California Rep. Jane Harman (D) will announce her resignation from Congress today, as NBC's Andrea Mitchell first reported yesterday. Here's Roll Call: "A torrent of spending is expected in a multicandidate field that will be the first Congressional race under the state's new top-two primary format. The top two finishers in the all-party primary would advance to the special general election, unless one candidate receives at least 50 percent of the vote. The timing isn't set, but the election most likely will take place before summer begins."
The New York Times: “Representative Jane Harman, Democrat of California, is leaving Congress to become president of the Woodrow Wilson International Center for Scholars, party officials said on Monday. Her seat, in a Democratic-leaning district of Los Angeles County, is likely to be filled by a special election.”