It's not just enthusiasm about the presidential candidates that is driving a surge in voter registrations in New Jersey, though that is certainly a factor.

State and county election officials say a letter sent by the state to more than 800,000 people who were not believed to be registered is a major cause for swelling voter rolls.

"This is part of what I think is an historic undertaking," said Ronald Chen, the state's public advocate.

The letters were sent by the Secretary of State's Office to settle a complaint by the Public Advocate's Office.

In 2007, Chen had employees make undercover visits to Motor Vehicle Commission offices and found that workers were not offering everyone the chance to register to vote, as required by a 1993 federal law.

The letters were intended to make it easy for nonvoters to register. They were sent with registration forms, already largely completed with personal information.

They went out throughout September to everyone who had conducted business at an MVC office since 2004 but was not registered to vote - and to many people who already were registered.

Among those who received letters were people whose names or birthdates did not match in the separate computer systems used to track driver's licenses and registered voters.

The first 300,000 or so letters - sent to people in Atlantic, Bergen, Burlington, Camden and Cape May Counties - caused some confusion because of their language, which began, "A review of our records indicates that you are currently not registered to vote."

People in the remaining 16 counties received a revised letter, ensuring them that if they had registered in the past, they remained registered.

Joanne Nyikita, the superintendent of elections in Burlington County, said her office received about 9,000 forms from those who got the letters. About 30 to 40 percent came from people who already were registered, she said.

Elections officials say they also are seeing more voter registration drives at places like churches and banks.

And it seems people are motivated to vote this year.

Raymond Knock, a retired railroad worker from Hamilton Township, went to the Mercer County Administrative Building on Tuesday to make sure he was registered.

He did not vote in the 2004 presidential election because he did not care who won, he said. This year is different. "I think we need change in this country," said Knock, 76, who would not say which candidate he prefers. "Someone's got to get us out of this hole."

Associated Press writer Samantha Henry contributed to this report.