>All you need is a majority within a party that gets half the vote: 50% of 50% is 25%. This is why the Republican party has been taken over by an extremist who'

>All you need is a majority within a party that gets half the vote: 50% of 50% is 25%. This is why the Republican party has been taken over by an extremist who's unpopular with large chunks of his own party. The plurality primary system actually makes it much worse than that. The total percentage of the registered voter population who nominated Trump, IIRC, was about 4.5%. It was 4.6% for Clinton, too. Lots of other people voted in the primaries, but voted for losing candidates. So it actually turns out you need 4.5% of the total voting population to support you to get a major-party ballot line, at which point you'll basically receive 25% in the general election on "ham sandwich" grounds in your party's regional bases. Then you can concentrate on competing your way up to a majority vote in the general (or for Presidential races, the Electoral College).