IRV ignored such a winner in a 2009 IRV mayoral race in Burlington, Vermont. In that election, Democrat Andy Montroll was favored over Republican Kurt Wright 56% to 44% (930-vote margin) and over Progressive Bob Kiss 54% to 46% (590-vote margin), majorities in both cases. In other words, in voting terminology, Montroll was a “beats-all winner,” also called a “Condorcet winner” – and a fairly convincing one.
However, in the IRV election, Montroll came in third. Kiss beat Wright in the final IRV round with 51.5% (252-vote official margin).
But some excuse the fact that IRV can fail to elect a Condorcet winner in such cases, claiming that the Condorcet winner didn’t have enough first-place votes. Advocates call these first-place votes “core support”. Here’s one perspective of that claim:
“Condorcet-type voting violates the principle of requiring a minimum level of core support by permitting a candidate to win who would not win a single vote in a plurality election.”