Former South Bend, Ind., Mayor Pete Buttigieg, left, and Vermont Sen. Bernie Sanders, right, in Iowa. After a year of intense campaigning, they finished in a virtual tie in the Iowa caucuses.

Former South Bend, Ind., Mayor Pete Buttigieg, left, and Vermont Sen. Bernie Sanders, right, in Iowa. After a year of intense campaigning, they finished in a virtual tie in the Iowa caucuses.