Meanwhile, the Democratic Party said there have been reports of Hispanic voters in Washoe County being called and told they could vote over the phone and not have to go to the polls. Party officials called the tactic a dirty trick intended to discourage minorities from voting.

Democratic spokesman Paul Kincaid said the callers, who spoke Spanish, purported to be from the Obama campaign, and their numbers were untraceable. He said the party was reaching out to its supporters to make sure they didn’t fall victim to such a ruse.

Similar calls have been reported in recent days in Florida, he said.

The Republican Party’s executive director, Zac Moyle, said the GOP was not behind the purported tactic and "wouldn’t condone that in any way, shape or form."

But Republicans are concerned that people who didn’t complete their voter registrations by the legal deadline are being allowed to vote alongside properly registered voters.

Poll watchers have observed people show up to vote, only to be told that their names are not in the registered voter database the state maintains. But some are then told that their names are on a separate list indicating that they filed registrations by the deadline, but the registrations were incomplete or erroneous, according to a letter Lowden sent to Secretary of State Ross Miller Monday afternoon.

Those people are then allowed to supply the missing or correct information and proceed to vote on a voting machine alongside everybody else.

The deadline to register to vote by mail was Oct. 4; registrations were accepted in person at election offices until Oct. 14.

Lowden’s letter contends the practice of letting people complete flawed registrations and vote is illegal because the registrations weren’t complete by the deadline.

"We believe that the persons who submitted the registrations at issue here may be ineligible to vote in this election and should not be voting by regular ballots, either during the early voting period or on Election Day," the letter states. It asks Miller to instruct all county clerks and registrars to require "any person who is not included in the statewide database as a registered voter and attempts to vote ... to cast a provisional ballot."

Provisional ballots are special ballots used to allow people whose voting eligibility is in question to cast votes that can then be counted (or discarded) later, after the eligibility question is resolved.

A spokesman for the secretary of state’s office said the office was working on a legal interpretation to clear up the question and expected to make a determination Wednesday.

Clark County Registrar of Voters Larry Lomax said the county was following its standard procedure in dealing with people who registered at the last minute and didn’t complete their forms.

The most common situations, he said, are people who forget to supply their birth date, forget to sign the form, or put down a mailing rather than a residential address.

Under Nevada statute, "if the county clerk determines that the application is not complete, he shall, as soon as possible, mail a notice to the applicant informing him that additional information is required to complete the application." The applicant then has 15 days to supply the information.

Some people who registered by mail by the Oct. 4 deadline didn’t have such notices mailed to them until Oct. 13, Lomax said, meaning their 15-day window to correct their registration has not yet run out. The county keeps an internal list of such people, known as "fatal pends."

There are about 1,400 people on that list, which shrinks with each passing day as more applicants’ 15 days expire. By Oct. 28, it will be down to zero, Lomax said.

If someone shows up to the polls believing he can vote but isn’t in the computer the poll workers consult — the statewide database — workers call headquarters to see if the person is on the "fatal pend" list. If so, the person is allowed to show identification and complete his registration, then proceed to the booth and vote.

"I’ve been here 11 years and that’s what we’ve always done," Lomax said. "As far as we know, it’s in accordance with the law. We’re not letting people vote who aren’t eligible." All the people in question made a good-faith effort to register by the deadline and are afforded a grace period in the statute, he said.

Lowden’s letter, however, contends that the 15-day provision "cannot extend the general deadline for voter registration expressly set by" statute.

GOP official Moyle said Republicans were not trying to suppress the vote.

"Our goal is to ensure that every qualified voter is able to cast a vote in a transparent and fair election, and ensure their vote is not wiped away by an illegally cast ballot," he said.