Republicans in Colorado on Monday pulled slightly ahead of Democrats, as ballot returns climbed a week into early voting, according to data compiled by the political scientist who runs the United States Elections Project.

With just over two weeks until ballots are due on Nov. 6, nearly 115,000 have been received and processed by Colorado election officials, reported Michael McDonald, an associate professor at the University of Florida, who is tracking early voting statistics across the country.

As of Monday, officials reported receiving 114,743 ballots – including ballots returned in the mail, deposited at 24-hour drop-off locations and cast in person at county clerk’s offices.

Of those, 41,577, or 36 percent, were cast by Republicans, while 39,861, or 35 percent, were cast by Democrats, and 31,947, or 28 percent, came from unaffiliated voters.

Colorado’s 3.3 million active, registered voters started receiving mail ballots last week, but the state’s roughly 26,000 registered military and overseas voters began getting their ballots in mid September.

Voters have been able to cast ballots at clerk’s offices since Sept. 22. On Monday, election officials opened vote centers in every county, which will be open through Election Day.

Secretary of State Wayne Williams announced Monday on Twitter that his office plans to start releasing ballot return numbers on Tuesday.

According to a report posted last week by Colorado Politics and figures compiled by the United States Election Project, ballots cast by registered Democrats outnumbered those cast by registered Republicans in Colorado through Saturday, but the GOP took the lead in Monday’s totals.

At the same point in the last midterm election – one week after ballots started going out in the mail and 15 days before the General Election – Republicans led by a much wider margin, although fewer ballots had been returned.

According to a report issued on Oct. 20, 2104, by the Colorado Secretary of State’s Office, 79,355 ballots had been received by that date. Republicans accounted for 36,830 of them, or 46 percent; 24,468 were Democrats, or 31 percent; and 17,191 were from voters registered unaffiliated, or 22 percent.

The 2014 election was a good one for Republicans nationwide and in Colorado, with the party ousting an incumbent U.S. senator and winning control of the state Senate for the first time in a decade.

NBC News reported Monday that Republicans were voting early in higher numbers than Democrats in seven of eight key states – not including Colorado – possibly hampering Democrats’ hopes for a “blue wave” in the midterm elections.

But election experts point out that Republicans tend to vote early – a pattern exhibited in Colorado’s June primary election.

It’s customary for election officials to warn against reading too much into initial ballot return reports, since Colorado’s 64 counties have different procedures for handling ballots. Some counties, for instance, empty drop-boxes early in the day, while others report totals before collecting and processing ballots.

Colorado residents can register to vote and cast a ballot through Election Day, but need to register by Oct. 29 in order to request a mail ballot.

Voters can update their registration, check out sample ballots, determine whether to expect a mail ballot and find places to vote in person or where to drop off ballots at www.govotecolorado.com.

UPDATE: The Colorado Secretary of State’s office reported Tuesday that clerks had received 159,312 ballots as of first thing Tuesday morning, including 57,695 from Republicans, or 36 percent; 55,450 from Democrats, or 35 percent; and 44,300 from unaffiliated voters, or 28 percent. Each party’s share of the total early vote remained the same as it was for Monday’s figures reported above.