As of Sunday, 523,938 Colorado voters had returned their ballots for the presidential primary election, the secretary of state’s office announced Monday. That represents 15% of the 3.4 million active voters.

There are just over 1 million active registered Democratic voters, and 980,000 registered Republicans. Nearly 1.4 million Coloradans are registered as unaffiliated. Included in those numbers are 17-year-olds who will be 18 by the general Election Day so are therefore eligible to vote in the primary election.

Nine days before the ballot due date, there have been 257,537 votes cast in the Republican primary and 202,079 cast in the Democratic primary, with more than 60,000 ballots received but not counted. In addition to President Donald Trump, five other GOP candidates appear on the Republican presidential ballot. There are 17 Democratic candidates, several of whom withdrew after the Jan. 3 deadline to appear on the ballot.

Former U.S. Rep. John Delaney and U.S. Sen. Michael Bennet submitted the requisite paperwork to the secretary of state’s office formally withdrawing, and votes for them will not be counted. Other candidates, including U.S. Sen. Cory Booker, Marianne Williamson, and former Gov. Deval Patrick, have also dropped out but did not complete the formal process in Colorado.

Of the nearly 148,000 unaffiliated voters who have cast ballots so far, nearly two-thirds chose to participate in the Democratic primary, among those ballots counted so far. El Paso and Jefferson counties have the largest number of ballots returned, at over 69,000 each. Jefferson is traditionally a swing county, and Trump held a rally in Colorado Springs on Thursday.

The deadline to return ballots is March 3.