The US state of Maine uses it. Also a few others like Alaska.

Maine has a phenomenal demonstration of how it should work in the governor’s race. The Fascist party got the most votes in the first round, but no a majority. As the round progressed the majority vote coalesced behind a consensus candidate, who won.

With FPTP, it would have been a hard right fascist governor. With STV, a moderate with broad support won.