"I believe there is fraud both ways. I don't think it's a specific group," said Kelley, a registered Republican whose group is called Tampa Vote Fair. "We're just there to observe. We're not going to intimidate anyone."
Poll watchers from unions, immigration groups and other organizations favoring greater voter access will also be on hand. Gihan Perera of the group Florida New Majority said training sessions are being held for observers and communications lines set up to respond to problems.
"We'll be aware and vigilant so that all of the rules and processes are honored and that our people are able to vote with ease," he said.
With polls showing a close race between President Barack Obama and Republican nominee Mitt Romney, a relative handful of votes either way in a battleground state like Florida or Ohio could make all the difference. The potential for disruptive crowds of observers at some precincts has sparked fears that voters may be intimidated or harassed or have their eligibility to vote challenged directly.
The concern is particularly intense among African-American and Hispanic voters, who historically have suffered discrimination and were targeted anew in more recent elections, civil rights leaders say.
"People have suffered and bled for our right to vote," said the Rev. Victor T. Curry, pastor of New Birth Baptist Church in Dania Beach, north of Miami. "We will have monitors who will monitor the monitors."
Groups such as True the Vote, a Houston-based organization with links to the tea party, refer to their activities as "election integrity." For those fearing suppression attempts, it's all about "voter protection." Both sides are organizing people around the country to be their poll watchers.
True the Vote has said it hopes to recruit 1 million people nationwide to be monitors. Its founder, Catherine Engelbrecht, said that her group is nonpartisan and that its goal is "renewing faith in our election system" through its growing national coalition.
"Every eligible American voter deserves the opportunity to participate in a fair and legal election process, even those Democrats and left-leaning organizations who continually cast false aspersions about our efforts," Engelbrecht said in an email. "We support lawful election processes."
Recent studies by New York University's Brennan Center for Justice and by the research and advocacy organization Demos show that voter intimidation and challenges are not relics from the past:
—In a 2011 state legislative election in Massachusetts, dozens of challenges were filed by poll monitors affiliated with tea party groups against Latino voters in Southbridge. Several voters said they felt intimidated in a vote that wound up in a court-ordered tie. Justice Department officials were on hand to observe the second vote, which was settled by just 56 votes.
—In 2010, a coalition of Minnesota conservative groups called Election Integrity Watch offered $500 to anyone who provided tips about fraud and encouraged volunteers to take photos and videotape voters at the polls, according to Demos research. It's unclear if these tactics were widely deployed or whether they deterred voters from casting ballots.
—True the Vote poll watchers used inaccurate voter lists to challenge a number of college students during the 2012 recall election of Wisconsin Gov. Scott Walker, resulting in a disruptive atmosphere in which an undetermined number of students opted not to vote rather than wait in long lines. The impact on the recall's outcome is uncertain, but Walker prevailed in the overall vote.
True the Vote's activities, especially its pre-election challenges of thousands of voter registrations, have drawn the attention of Democratic members of Congress, including Rep. Elijah Cummings, D-Md. Cummings said in a letter to Engelbrecht that many of the challenges appear to have no legitimate basis and "could amount to a criminal conspiracy to deny legitimate voters their constitutional rights."
In a written response, Engelbrecht offered to meet with Cummings and said the group has found evidence of election law violations.
"Election integrity is a serious concern across the nation," she wrote.
States have specific rules regarding who is allowed inside polling places and how close outside observers can get. In Florida, those on the outside must stay at least 100 feet away. Most states also allow private citizens to directly challenge the eligibility of voters—for example, claiming they don't have proper identification—although not all of those challenges can be made on Election Day.
Federal and state agencies also play a role in poll monitoring. The Justice Department, for example, will appoint observers under the 1965 Voting Rights Act who are geared mainly toward guaranteeing that minority voters are not interfered with at the ballot box. This third group of monitors will be sent to precincts that officials deem most at risk of voting access violations.
"The effort in more recent years is to have teams in place and procedures in place so problems can be dealt with," said Paul Hancock, a former Justice Department voting rights attorney now in private practice.
At the same time, Hancock added, "you've got to have balance. You want to be able to deal with any group that comes in and tries to intimidate voters. But you don't want the place loaded with police officers because some people see that as a form of intimidation as well."
If any violations such as those happen this year and the election result is close in that particular state, teams of lawyers from both sides and many of the interest groups are posed to head to the courts.
"Everybody is just so concerned that something could go wrong that they're geared up to deal with it," Hancock said.
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