Democrats' registration efforts are drawing close scrutiny this year as the party remains determined not to lose another presidential election as close as the one in 2000.

With an especially intense get-out-the-vote (search) effort this year, Democrats are registering new voters faster than some states can keep up with them.

In states like New Mexico, which the president lost by the narrowest margin in the last election, officials say registrars have no room for error.

"The last election, it was 366 votes [that] separated them," said New Mexico Republican Sen. Pete Domenici (search). "If it's anywhere close to that, you can count on it, this registration drive will turn it against the president."

Overwhelmed by new registrations in Ohio, the Republican secretary of state is threatening to invalidate forms that weren't on heavy cardboard stock. Ohio Republicans suspect fraud, and authorities are investigating registration forms they say appear to involve non-existent addresses, dead people and different names in the same handwriting.

To try to prevent fraud at the polls, a 2002 law requires voters who don't register in person to show identification at the polls. But Jim Jordan of the Democrat-leaning America Votes (search) says such a policy is suggestive of voter harassment.

"Unfortunately, in this country, there's a history of harassment at the polls," he said.

Click in the box near the top of this story to watch a report by FOX News' Wendell Goler.