More than half the state's active registered voters have cast early or absentee ballots, according to state and county statistics.

Clark County election officials reported problems at the Mountain View Elementary School polling station this morning.

Voting machines at the northeast Las Vegas school were not running until after 7:30 a.m.

Ed Garcia, an observer for the Barack Obama presidential campaign, said observers at the site saw some frustrated voters leaving.

The machines were running properly by 7:45 a.m.

The county registrar's office reported no other problems when polls opened today.

County voter turnout is on a pace to set a record, Registrar of Voters Larry Lomax said two hours after polls opened.

"There's not question. We are on pace to have a record turnout. No doubt about it," Lomax said.

He said if those who vote today total 250,000 in the county, then that combined with early voting and absentee ballots would put voter turnout at 85 percent, which he said would be unprecedented.

About 100 people lined up this morning at Staton Elementary School in the northwest valley, where voting was steady and smooth.

Starr Moore, who was voting for the first time in Nevada, said the long line was unexpected.

"I didn't think the line would be so long because of early voting," said Moore, who came here from Northern California.

Richard Marston, who was about the 100th person in line, said he was prepared for the line to be long.

"It's a big election," Marston said.

The polls will be open through 7 p.m. today throughout Nevada.