WASHINGTON— Millions of inaccurate and invalid names clutter voter registration rolls in the United States, according to a study released Monday by the Pew Research Center.

Data from the report show that approximately one in eight active voter registrations are defective due to outdated information. Death, mobility and a lack of general knowledge of how the voter registration processes work are to blame, said David Becker, director of Pew’s Election Initiative.

“There is absolutely no evidence that any of the inaccuracies led to voter fraud or suppression but it does underscore the need for an improved system,” Becker said.

During the 2008 elections, more than 2 million provisional ballots were issued after voters encountered problems at the polling places. The Pew study found that most of these voters were unaware they needed to re-registrar or update their information.

To combat such problems, the study suggests that states switch to an automatic registration system, which would rely on data bases linked to driver licenses and Social Security numbers. Citizens would no longer need to request forms, fill them out and mail them back. Instead, they would need to log onto the appropriate website and fill out an online form.

“This would create better information for election officials and make it easier for them to reach out to those people who appear to be eligible voters but are not on the [registered voter] list,” said Becker.

Additionally, it would reduce “unwarranted cost drivers,” like processing fees and printed forms, said Becker.

According to the study, Arizona saved $1 million over five years when it switched to an automatic voter registration.

“It takes up far less staff and resources to process,” said Becker. “Just think, with a paper registration system there is just a tremendous amount of paperwork needing to be processed before an election. It’s impossible.”

Eight states currently use this new, computerized voter registration system. Becker hopes three or four more states will switch by the 2012 election.

“Its convenient and efficient for both Oregonians and election officials,” said Kate Brown, Oregon’s secretary of state. “People are updating their information effortlessly and seamlessly because they are using the tools they are already familiar with.”