For the purpose of determining the number of convictions under 45-6-301, a conviction means:
(1) a conviction, as defined in 45-2-101, under the same statute;
(2) a conviction for a violation of a similar statute in another state; or
(3) a forfeiture of bail or collateral deposited to secure the defendant's appearance in court in this state or another state for a violation of a similar statute, which forfeiture has not been vacated.