UPDATE, 6:30 p.m.
Turnout lagged at two large precincts in West Boise, where voters cast ballots at Ustick Baptist Church on McMillan Road.
With two hours until polls close at 8 p.m., turnout was 10.4 percent of about 3,850 registered voters.
A handful of citizens complained about the new law requiring voters to declare their party affiliation, but most took the change in stride, said chief judge Katie MacDonald.
"We've had a couple that were offended," MacDonald said. "They don't want to out themselves. But it's not what we expected."
GOP voters were drawn to two hotly contested House races in Legislative District 20, but some also considered protecting the delegates won by Mitt Romney for the presidential race a top priority.
Dave Tuttle said he thinks Romney is far more likely to unseat President Obama than Ron Paul. Some Paul supporters are working to overturn the results of the March GOP caucus, which awarded all 32 Idaho delegates to Romney.
Tuttle said he voted for Romney loyalist Peggy Moyer for precinct committeewoman over Daniel Malloy.
"Ron Paul has some great ideas, but I don't want to see Barack Obama again as president," Tuttle said.
Election officials are reporting unusually slow turnout, with Idaho Secretary of State Ben Ysursa predicting the new closed primary will prompt the lowest voter participation in history.
“I hope I’m wrong, but I’m predicting 23 percent,” Ysursa said about 3 p.m. Tuesday, with five hours left in the voting day. “Turnouts are made between 5 (o’clock) and 8 o’clock, so we’ll see.”
The record low turnout for a primary was in 1988, when 25.03 percent of registered voters cast ballots.
“I personally believe the main reason will be the angst and reluctance to declare a party,” said Ysursa, a Republican who has helped administer Idaho elections since 1975.
Idahoans are now required to affiliate with the GOP to vote in the primary, thanks to the Idaho Republican Party’s winning a lawsuit in federal court, which convinced a reluctant Legislature to change the law last year.
The decision to close the primary is up to Idaho’s four political parties, Republican, Democrat, Constitution and Libertarian. Democrats left their primary open to members of other parties and independents, but have few contests on the ballot outside of Boise’s District 19. Which party voters affiliated with and voted for is a public record in Idaho for the first time.
Turnout was 27.07 percent in the 2010 primary. The high mark was set in 1980, when 43.34 percent of registrants voted on a ballot that included Ronald Reagan for president and the historic Steve Symms-Frank Church U.S. Senate race.
Ada County Chief Deputy Clerk Phil McGrane said he and Clerk Chris Rich toured eight or nine of the county's 145 precincts this morning and afternoon.
“Consistently, turnout was slow,” McGrane said. “I honestly don’t know why. Perhaps people just aren’t happy with the closed primary and don’t want to participate.”
McGrane added that voters are reasonably well acquainted with the new rules. “They may not like the process, they may complain, but they are informed voters and understand the new process.”
McGrane attributed that to efforts by Ysursa’s office, county clerks and the media to inform voters of the new requirements.
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