I.R.V. is a system intended to help third party participation in a two-party system. Voters choose a first choice, second choice, and third choice. If their first choice loses, their vote transfers to their second choice candidate. For example, in 2000, voters might have voted first for Nader and second for Gore -- allowing more expression of political preferences while eliminating the "spoiler effect." I.R.V. systems are in effect in several nations abroad, and also in numerous municipal elections in the U.S.