There is both a huge advantage and a huge DISADVANTAGE.

The advantage is that there is naturally more of a choice. Which means that voters would have to go with “the lesser of two evils” MUCH less often.

The disadvantage with having more than two viable parties is that it then becomes much harder for one party to GET an outright majority on a first ballot of anything.

In Parliamentary countries, this means having to settle for coalition governments that tend to fall apart after a few months or even after a few weeks.

The the US, having several viable parties would MEAN that even with the electoral college, everyone might fail to get a winner of the majority of electors, which in turn would mean that presidential elections would be decided in the House of Representatives… assuming the House could reach a decision and not get deadlocked as it was in 1800. But in any case, that’s a really stupid way to elect a president.

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