The Republican Party in Utah used Instant Runoff Voting this week to elect a replacement for a state senate vacancy in a seven-candidate race. Indeed about a half dozen current Republican state lawmakers first won office in a similar way. In 2004, the state convention used IRV when former governor Jon Huntsman was first nominated.
Account of this week's election
Round by Round results from Davis County Republican Party
Article about past use of IRV to fill 2009 vacancy
Articles & analysis of 2002 & 2004 state conventions using IRV
Article on Utah testimony on adopting IRV for state offices