The runoff primary has been variously dubbed the "second primary," the "second ballot," the "double primary," the "run-over primary," or the "dual-primary system." A primary is an electoral contest held to choose a party's nominee for public office. The nominees selected in this manner by the various parties (in the United States, usually the Democratic and Republican parties) then stand before the public in a final vote, which determines the officeholder. At the turn of the century, reformer-leaders of the Progressive movement advocated the primary as a means for opening up the process of leadership selection to rank-and-file voters. Before the advent of the primary, party bosses had enjoyed the luxury of handpicking their favorite nominees—often mere toadies—through secret negotiations in the now-legendary smoke-filled (and bourbon-scented) back rooms of party headquarters.
Under the runoff variation of the primary, if no candidate for nomination receives a majority of the votes cast, he or she is then required to face the second-place finisher in another election held a few weeks later (the runoff). In this narrowed two-person contest, the eventual nominee is guaranteed the opportunity to boast of majority support within his or her party, rather than having to confront the opposition party in the general election with a weaker plurality vote—indeed, perhaps only a sliver of victory in the balloting for nomination.
In plurality elections, the candidate who receives more votes than anyone else is declared the victor—the first past the post wins all. In contrast, the demo