Transportation Secretary Ray LaHood, the last Republican left in President Obama’s Cabinet, announced Tuesday he is stepping down.

In a note to department staff, LaHood said he would remain at the helm until a replacement is confirmed to ensure “a smooth transition for the department and all the important work we still have to do.”

The former seven-term congressman from Peoria, Ill., has led the department since 2009 and was not expected to stay on through a second term. Among those who have been prominently mentioned as a possible successor is Los Angeles Mayor Antonio Villaraigosa, whose mayoral term ends June 30 and who played a key role in writing a provision of last year’s federal transportation bill that is designed to speed up projects throughout the country, including in Los Angeles.

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