Voters this year may have avoided voting straight-party Republican because of popular Democratic candidates in county and legislative races, he said.
Ziriax said an individually marked race always overrides straight-party voting.
“The straight party will vote everything that's not marked, but if you go mark one differently that always, always overrides a straight-party,” he said.
By the numbers
In 2008, the number of straight-party votes for state officers dropped off by 13,000 votes; 671,348 voted straight-party for state officers. Republicans dropped from 59.5 percent in the presidential to 56.5 percent in the statewide and Democrats picked up 3 percent, from 40.5 to 43.5 percent.
In 2010, state Election Board records show that nearly 100,000 more Republicans than Democrats voted a straight-party ticket in the ballot for statewide races, resulting in GOP statewide candidates getting nearly a 100,000-vote cushion.
Of voters casting straight- party votes on statewide races, 61.8 percent voted Republican, or 256,801 and 38.2 percent, or 158,775, voted Democratic.
About 40 percent of the votes received by Gov. Mary Fallin were straight- party Republican ballots. The percentage of straight-party voters supporting one party in statewide elections in 2010 was the highest in recent years.
In 2008, 56.5 percent of the straight-party ballots were cast for Republican statewide candidates and in 2006, when Democrats won eight of the nine statewide offices, 58 percent of the straight-party ballots were cast by Democrats.
Tuesday's turnout was about 63 percent of the state's 2.1 million registered voters. The turnout was below the 67 percent recorded in 2008 and the 68 percent that voted in 2004, which was the highest number of voters in Oklahoma to cast ballots in a presidential election.
Gaddie said he expected straight-party voting will likely increase in the years ahead. The number of registered Republican voters, who are more likely to vote straight party, is continuing to grow in the state.
“The Democratic electorate is older and they've been in the habit of voting a split ticket for a long time,” he said. “The Republicans are a younger to middle-age voter and Republicans historically are a little more partisan than Democrats. They're less inclined to split their ticket.”