The core of the border city of Nogales is a busy downtown filled with Mexican shoppers. A steady stream of semi-trucks criss-cross the highway to the border and back.

Santa Cruz County surrounds Nogales. It’s made up of tourist spots, an artists’ colony, a winery and cattle ranches spread across fields of tall yellow grasses. The numbers out there, you’ll see in a bit, are very different.

Mexican culture dominates Nogales. More than 90 percent identify as Latinos. Its politics are extremely local and voter turnouts are extremely low.

In the 2010 midterm elections, the downtown precinct, basically, Nogales itself, reported a 29 percent voter turnout. That’s compared to the national turnout rate of 38 percent. Both were low, but Nogales was significantly worse.

For 20 years, Yvonne Ragland was chairwoman of the Democratic party in Santa Cruz County. She says the low numbers depress her.

"I’ve seen people who are not even aware that there’s an election going on on election day. They have no idea that it’s time to go vote," she said.

The political parties here will open offices to the public, hand out fliers, even drive people to the polls. But they haven’t been able to build up much voter participation, Ragland said. This year, with a presidential election, she expects the numbers will be even lower.

“And they will skip over like the presidential, Congress ... a lot of these important issues. They have no idea what it consists of," she said.

Some, like Antonietta Monaran, are lawful permanent residents who can’t vote. Monaran has lived in Arizona for four years but she says she hasn’t become a naturalized citizen.

She says hasn’t made the time to study to become a citizen. The Homeland Security Department estimates there are about 8 million like her in the country, a significant portion of whom are Latino.

Others say they are just too busy.

Juana Lerma was loading groceries into the trunk of her car in the Safeway parking lot. She used to be one of those people who drove the elderly to the polls on election day.

"Right now, I don’t even know who the candidates are. Why would I lie?" she said in Spanish.

She recently bought a small house and is busy working, with no time to care, she says.

Nogales' voting numbers are reflected across the country. Latinos could influence the national vote.

But while the number of registered Latino voters grew from 9 million to 11.5 million between 2004 and 2008, the numbers fell off by more than a half million in 2010 despite a growing Latino population. That means there is plenty of people who could vote but haven't registered, according to the William Velasquez Institute, which studies Latino voter turnouts.

"We have a much higher percentage of young and poor people, and young and poor people across all ethnic groups in the United States vote less," said Institute president Antonio Gonzalez.

His analysis seems to hold true in Santa Cruz County. Compare those voting numbers in Nogales, 29 percent, to the outlying ranching towns of Santa Cruz County with affluent neighborhoods and retirees from across the country.

In Sonoita, in the 2010 election, voter turnout was 82.8 percent.

Richard Cardillo, a precinct committee for the Republican Party Party in Nogales who has helped organize the Tea Party vote, has advice for places like Nogales where apathy is strong.

"You’ve got to get the knowledge. You’ve gotta know what you're talking about and you’ve got to learn the issues," he said. "People are so wrapped up in their own lives and their own problems that government has become a secondary thing. We all sit back and complain how the government is run and blame politicians but we don't want to do anything about it."

Fronteras Desk is a multimedia collaboration among seven public radio stations in Arizona, California, Nevada, New Mexico and Texas, including Arizona Public Media. Its reports air on NPR 89.1 and can be seen at azpm.org.