And the US has primaries. Last year there were 17 Republicans all trying to win their party's nomination in a series of open votes; out of those, the eventual winner, Donald Trump, was perhaps the candidate least liked by the party establishment.

If anything, the problem was too many candidates, combined with a first-past-the-post system. The majority of primary voters disliked Trump, but were split between several preferred candidates (who I group because they were far more similar to each other than to Trump). Trump got a certain segment of the vote all to himself.