WINSTON-SALEM, N.C./NEW YORK (Reuters) - North Carolina extended voting times in several precincts during Tuesday’s presidential election but Colorado rejected a bid to keep polls open longer after both states experienced problems with electronic voting systems.

Voters fill out their ballots on election day for the U.S. presidential election at Elevation Fire Station in Benson, North Carolina November 8, 2016. REUTERS/Chris Keane

In North Carolina, advocates including the National Association for the Advancement of Colored People had urged the state to extend voting time in eight Durham County precincts until 9 p.m. EST, an hour and a half past normal closing time. Instead, the state board extended voting time by an hour in two precincts and less than that in the other six.

In Colorado, the Democratic Party filed a petition in the Denver County District Court to extend voting for two additional hours after service failures in the state’s electronic voting system in some polling places. A judge denied the request and said polls would close at 7 p.m. CST as scheduled.

Colorado and North Carolina are both crucial battlegrounds in the U.S. presidential election between Republican Donald Trump and Democrat Hillary Clinton.

The Colorado Secretary of State office had opposed the extension of voting hours.

“This outage didn’t stop anyone from voting. We have had two weeks of voting and everyone got a ballot,” Lynn Bartels, a spokeswoman for the office, said on Twitter. She said anyone still in line when polls closed would have an opportunity to cast their ballot.

The Reverend William Barber, president of the NAACP in North Carolina, told members of the State Board of Elections on a conference call Tuesday evening that their refusal to extend voting hours as long as requested by local elections officials was “deeply concerning.”

The problem in North Carolina involved the electronic poll books used to check in voters in some precincts. At one precinct where voting was extended for 60 minutes, election officials reported there had been up to a two-hour period earlier in the day where no voting took place.

“We’ve fought too much voter suppression in this state over and over again,” Barber said.

Patrick Gannon, spokesman for the North Carolina State Board of Elections, said voting was extended in just a handful of the state’s 2,704 precincts. The election board is made up of three Republicans and two Democrats.