DENVER – Hundreds of ballots for this year’s primary elections in Colorado won’t be counted because some unaffiliated voters have not followed the rules.

The Denver Post reports that unaffiliated voters can only send back a Republican or Democratic primary ballot – not both.

As of Friday, the Denver Elections Division says that of the 6,185 unaffiliated voter ballots received so far, 3.4 percent – or 214 – have been rejected because voters tried to cast ballots in both primaries.

In Larimer County, the percent of rejected ballots for the same reason is 3.15 percent, while it’s 4.3 percent in Arapahoe County. In El Paso County, 7 percent of unaffiliated voter ballots have been rejected.

Elections officials have been trying for weeks to get the word out about the rules for Colorado’s first open primary.