South Bend, Ind., Mayor Pete Buttigieg was on a quest to reform the Democratic Party nearly 15 years ago, while at Oxford University in England. He opposed centrism at the time, a political space he has moved into as his 2020 presidential campaign has taken off.

South Bend, Ind., Mayor Pete Buttigieg was on a quest to reform the Democratic Party nearly 15 years ago, while at Oxford University in England. He opposed centrism at the time, a political space he has moved into as his 2020 presidential campaign has taken off.