Courtesy photos For different reasons, Suzann Holland, of Monroe, Wis., Heather Felton, of Parrish, Fla., and Ryan King, of Buffalo, N.Y. will not be voting in the Nov. 6 elections.

Tabitha Brown, 29, of Oregon, says she won't vote because she finds her ballot too confusing. “I’m just a simple girl," she said. "Dumb it down for us.”

In Buffalo, N.Y., Ryan King, 19, said he won't vote because he doesn't know if he's registered. He mailed in a registration form, but no one replied, so he doesn't know where to show up. Further south in the Bronx, Lala, a woman who is staying at a shelter, isn't voting because she thought she needed a state ID, which she can’t afford. When she learned she didn’t need an ID, it was too late to register.

Political pundits say undecided voters will determine the election, but little is said about people like Brown, King and Lala, who aren’t voting. Since the 1960s, voter turnout has steadily declined in the U.S., which already ranks near the bottom among established democracies. In 2008, 64 percent of voting-age citizens voted, compared with 93 percent in Chile, 86 percent in Germany and 74 percent in Canada.

In this election, the fear is that some nonvoters may have wanted to vote. In Florida, voters cried out in frustration as polling stations became overwhelmed, and the Democratic Party had sued to extend early voting after some people were stuck on lines for hours trying to meet Saturday's deadline. NBC's Michael Isikoff reports.

NBC News recently asked readers via Twitter, Facebook and through NBCNews.com to tell us why they won't cast their ballots. Their responses paralleled those from a 2008 survey by the U.S. Census Bureau: They don’t like their choices, they’re busy or they’re not interested.

Broken down, the least likely voters have the lowest level of education. In fact, the most pronounced voting gap in 2008 was not between young and senior (49 to 72 percent) but between those without a high school degree and those with advanced degrees – 39 percent to 83 percent.

The wealthier are more likely voters -- 52 percent of those whose annual family income is less than $20,000 voted versus 80 percent among those whose families bring in more than $100,000. That could be partly because low-income people have more trouble taking time off work to vote.

“Everyone’s pressed for time these days and therefore whether or not an employer is actively allowing people to vote the employees may feel time-pressed or constrained to take that legally protected time,” said Susan Schoenfeld, senior legal editor for Business & Legal Resources, which provides guidance to employers on human resources issues.

Although some states require that employers give workers time off to vote, human resource experts say those laws are sometimes too confusing for employers and employees to understand.

About 13 percent of those responding to the Census survey said they didn’t vote because they didn’t like the 2008 candidates. That theme emerged among our readers too – many of them women in their 30s and 40s – who said not voting was itself political. Leaving their forms blank was, in a sense, a vote of no confidence.

“It feels like a third choice,” said Suzann Holland, a 41-year-old public library director from Monroe, Wis. “We tend to think we have two choices because third parties are not viable, but there is a third choice – to let other people decide because sometimes either choice goes against everything we believe in.”

Holland has voted in the past but this year, she said the debates between President Barack Obama and former Massachusetts Governor Mitt Romney “cemented my distaste for both candidates.”

Breeanne Findley, 32, of Moline, Ill., is also fed up with Obama and Romney. She and her husband have five children between the two of them; she is a stay-at-home mom and is devoutly Pentecostal.

“I kept going back and forth, I looked online at who else was running for president – the Green Party and some other independent groups – but I didn’t like those guys either,” Findley said.

Her sister-in-law was appalled, she said. “She says that I’m not allowing my voice to be heard, saying that I should reconsider because my vote matters, there these are things I need to be voting for.”

She has decided it doesn’t matter who becomes president: “I’m a Christian and I believe that God is in charge. If this guy wins, it’s not the end of the world because God is still God.”

In Parrish, Fla., Heather Felton, 37, said she found herself lost in the political middle. She is Catholic, opposed to abortion, but also opposed to the death penalty and in favor of gun control. She has nuanced views about immigration.

“I posted to my Facebook page, ‘Who should I vote for? Give me a good moral reason,'” she said. “But people aren’t giving me a good moral reason. They’re presenting negative inflammatory language.”

NBC's Tom Brokaw speaks with young voters grappling with a distrust of the political system.

Back in New York, King, a student at Cansius College, is not alone in struggling with registering to vote. Six percent of nonvoters between the ages of 18 and 24 didn’t vote in 2008 because they didn’t know how or where to sign up, according to the Census data.

After mailing in a voter registration form, he looked online for clues about where he should vote. He asked the College Democrats and the College Republicans at his school, but they told him they didn’t know.

Increasingly jaded, King now questions whether his vote would count. (Which lands him in another Census category: Four percent of nonvoters said they didn’t register because they didn’t believe their vote would make a difference.)

“I just feel so disenfranchised voting in New York,” he said. “It doesn’t matter anyway. If I voted for Obama, it wouldn’t count, so why bother?”

He added: “If you want me to vote so bad, at least meet me halfway.”

In the Bronx, Lala was slightly sheepish to find out she didn’t need an ID to vote. (She used to live in Georgia, where ID is required.) But mostly, she said, she feels increasingly apathetic. More pressing was food for dinner and ultimately, a job. She checked her wallet – she had $30 to her name.

She said she read Romney’s five-point plan but found it lacking and disjointed.

“As much as I would love to be bitter about living in poverty during the Obama administration, I have to consider that the alternative is a man without a plan,” Lala said. Then she grew contemplative.

“All I need is something as simple as a job,” she said. “I could have my quality of life back. I don’t know how voting is going to meet my immediate needs.”

NBC's Allison Linn contributed reporting to this story.

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