Success rate of the Iowa and New Hampshire presidential primary winners 1976-2016

Although much is said about the momentum a presidential candidate can gain from winning the Iowa and New Hampshire presidential primaries, in less than a quarter of cases between 1976 and 2016 has the winner gone on to beat the incumbent and become the new president of the United States. Over this time, New Hampshire has been a better indicator of success than Iowa, selecting the new U.S. president 25 percent of the time for Republican candidates and 22.2 percent of the time for the Democrats. This compares to 12.5 percent and 11.1 percent respectively for Iowa.These calculations do not include those primaries where an incumbent president ran unopposed.

尽管众说纷纭，关于总统候选人凭借赢得爱荷华州和新罕布什尔州总统初选而获得的动力，但在1976年至2016年间的不到四分之一案例中，胜者继而在竞选中击败现任总统并最终成为美利坚合众国新总统。在此期间，新罕布什尔州在预测成功方面优于爱荷华州，对于共和党候选人而言，其正确预测率达到了25%，而对于民主党候选人，这一比例为22.2%。与之相对的是，爱荷华州的正确预测率分别为12.5%和11.1%。这些计算并未包括那些现任总统未遇挑战的初选案例。