So why don’t we have a “two-and-a-half-party system” in the U.S.? It turns out American third parties are further limited by another plurality-based electoral component those countries don’t have: presidential elections decided by the Electoral College.

Almost every state uses a winner-take-all approach for awarding electoral votes,2 whereby the winning candidate will get all electoral votes by finishing first, regardless of whether that’s with 70 percent or 35 percent of the vote. So, in other words, the electoral system for our most high-profile national office makes it even more imperative to stitch together large coalitions. For instance, if the GOP were to split fairly evenly because of a Trump-led alternative, the result would likely be Democratic victories across most states. Yes, perhaps even states as red as Alabama or Utah, where President Biden only won about 37 percent of the vote last November.

Consider what happened in the 1912 election, when a conservative-progressive split in the GOP between President William Taft and Progressive Party nominee Theodore Roosevelt allowed Democrat Woodrow Wilson to win all but eight states despite winning only 42 percent of the vote nationally — including a state like Massachusetts, which Wilson carried with just 36 percent of the vote. So even if Trump did lead a third-party exodus from the GOP ahead of 2024 — and polls have suggested such a party could attract meaningful support —the reality is such a split would probably not be successful and would likely compel a Republican reconciliation in some form afterward, as was true following the 1912 election.