Hillary Clinton has so far won more states (18 versus 14) and amassed more pledged delegates (1,243 versus 975, per our delegate tracker) than Bernie Sanders, yet history favors the Vermont senator's grassroots campaign. The states he's won so far have correctly predicted the eventual Democratic nominee 65 percent of the time on average since 1968, according to a study of Federal Election Commission data by American University’s online analytics master’s program. That compares to 61 percent on average for states in Clinton's column.
Sanders' historical odds are buoyed by victories this past week in Idaho (75 percent track record) as well as Washington and Hawaii (both 71.4 percent). Clinton, meanwhile, has won just one state since her March 15 blowout and that's Arizona, which is the fourth-least predictive state (37.5 percent) on the Democratic side.
Looking ahead, Sanders is expected to win the April 9 caucuses in Wyoming, which has correctly predicted the eventual Democratic nominee 88.9 percent of the time, second only to Sanders-supporting Kansas (100 percent). After that come a series of big-state primaries that have so far favored Clinton. Top of the list: New York on April 19, where Sanders was born and Clinton served as U.S. senator, and which has correctly picked a Democratic nominee three out of four elections.