Answer
Yes, many states have adopted RCV for use in some elections. Maine has even adopted it for statewide and presidential elections. The map below is taken from FairVote.org and shows the states that have adopted RCV in some capacity. Check the FairVote website for more details on how RCV is being used in these states.
In addition, many colleges and universities, and private organizations use RCV. For a list of other organizations using RCV, see FairVote website.