President-elect Joe Biden is expected to pick former South Bend, Indiana, mayor Pete Buttigieg to head the transportation department. That's according to three people familiar with the plans who spoke on condition of anonymity Tuesday to avoid preempting the president-elect's announcement. The 38-year-old Buttigieg was one of Biden's rivals for the Democratic presidential nomination. He was a breakout star of the primaries, sharing victory in the nation's first caucus with Bernie Sanders. He suspended his campaign before Super Tuesday and endorsed Biden. The Transportation Department helps oversee the nation's highway system, planes, trains and mass transit and is poised to play a key role early in the incoming administration.