Hundreds of voters in the state’s most populous counties signed oaths attesting to their identities rather than offer a state-approved ID in order to cast a ballot in Iowa’s June 5 primary elections.While only a small share of the overall turnout, the numbers provide a glimpse into how many Iowa voters were required to take that extra step as the state’s new voter ID law began for the first time to roll out.Iowa voters now must present a state-approved form of identification when voting.