With three hours to go before the voting deadline in Colorado’s primary election, 983,703 voters had already cast their ballots.

And for the first time in a Colorado primary election, that total included a sizable number of unaffiliated voters.

Colorado Secretary of State Wayne Williams – the overseer of statewide elections – said that as of 4:10 p.m. Tuesday, 385,470 ballots had been cast by Democrats, 362,590 by Republicans and 235,643 by unaffiliated voters.

That’s out of about 3.8 million registered voters in the state.

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For the first time, under an initiative that passed in 2016, the state’s 1.2 million active unaffiliated voters had the option of choosing to vote in either the Democratic or the Republican primary, helping to nominate those party’s candidates for governor, Congress and the state legislature. Unaffiliated voters received both parties’ ballots but were allowed to return only one.

As of Tuesday at 4:10 p.m., 119,150 unaffiliateds had returned Democratic ballots and 75,593 had returned Republican ballots. Ballots from another 40,540 unaffiliated voters had not yet been opened, so the party preference had not yet been determined.

At that hour, women were outvoting men, 525,520 to 452,589, Williams’ report said.

There also was a sizable gender split between parties. Women were voting more for Democrats than for Republicans based on ballot returns by 4:10 p.m. (230,682 to 180,890) while men were leaning Republican by a lesser margin (180,588 to 152,504).

Williams said his office invested $900,000 in educating unaffiliated voters about the change in voting rules allowing them to take part in the primary without declaring a party affiliation.

“Citizens who make decisions here typically vote both Democrat and Republican. They’re used to being able to pick a Democrat for one office and a Republican for another office,” Williams said. “My goal has been to keep the disqualification rate as low as possible.”