A shift in attitude toward transit among metro Atlanta voters, including in counties that traditionally oppose MARTA, such as Gwinnett and Cobb, could be pivotal in whether next year's transportation sales tax referendum passes, according to a new poll.

Underlying issues including concerns about crime and whether the government can be trusted to oversee the work exist, according to a poll of 625 registered voters that Mason-Dixon Polling & Research Inc. conducted for The Atlanta Journal-Constitution and Channel 2 Action News. But they don't seem to be as big a problem as they may have been in the past.

And much of the opposition heard during recent community forums -- especially from tea party activists -- does not reflect voters as a whole, who at this point support the referendum's passage by a razor-thin margin.

“I think people’s experience plays a role, particularly in my area, where we have a lot of younger, newer folks coming here from other parts of the U.S. and the world who are used to having choices in transportation,” said state Sen. Doug Stoner, D-Smyrna, a transit advocate.

Debbie Dooley, a Dacula resident and co-founder of the Atlanta Tea Party, disagrees, and thinks the poll numbers are "drastically off." She hopes supporters of the tax believe the poll, she said, "because they’re going to be in for a rude awakening on Election Day. We have not yet begun to educate voters."

The draft project list would put about 55 percent of the tax money toward public transportation, which Dooley believes is about 30 percent too much for the region to stomach.

Transportation referendums will be held in each of 12 regions across the state next year, most notably in metro Atlanta.

There, voters in 10 counties will be asked to approve a 10-year, 1-cent sales tax. It is expected to raise $7.2 billion, $6.1 billion of which is to be spent on projects of regional significance.

Overall, the poll shows 51 percent of metro voters would vote for the referendum if it were held today. An additional 13 percent were undecided. In Cobb and Gwinnett counties alone, at least 48 percent were in support, with an additional 10 percent undecided.

A deeper look at the numbers, however, shows an increasing recognition of the price of inaction.

Overwhelmingly, 91 percent of voters said it was important to address the region's transportation problems to improve its quality of life and economic future. Additionally, 67 percent said the region's traffic congestion is deteriorating their quality of life. And 82 percent said it was important to do more to encourage everyone to commute to work by bus or train.

In the northern suburbs, some of the support is due to changing demographics. In the almost five decades since the original debate to create MARTA, Cobb and Gwinnett counties have become vastly different areas. More than a half million residents have moved into each county since 1960. More cars choke the roads, with no in-county access to trains run by the transit agency.

The Legislature created MARTA in 1965. That year, voters in Clayton, DeKalb, Fulton and Gwinnett counties approved local referendums ratifying their counties' membership on the MARTA board of directors; Cobb voters rejected participation. In 1971, DeKalb and Fulton voters also approved the collection of a 1 percent local sales tax to support transit operations and help finance rail construction. Gwinnett voters rejected the tax that year (and hence MARTA service). In a November 1990 referendum, Gwinnett voters again rejected MARTA -- a sentiment that remains strong among some in the county.

"I'm not in favor of raising taxes to support anything with transportation and roadways," said Mary Haymon, a retiree who lives in Suwanee. "I don't feel the taxpayers should have to take that on."

Yet from 2000 to 2010, Gwinnett’s population jumped almost 37 percent while Cobb’s population increased 13.2 percent. And perhaps more notably, the once mostly white suburbs have noticeably diversified.

In Gwinnett, over the same 10 years, whites dropped from about two-thirds of the population to less than half. In Cobb, whites fell from 72 percent in 2000 to 56 percent in 2010.

Why does that matter?

"MARTA was being created at the time during the civil rights movement and desegregation throughout the South, and those issues and white flight definitely played into it," Stoner said. "Race was a factor, and over time the term used a lot of time was 'crime.' "

Today, 57 percent of voters said they don't agree an increase in mass transit means more crime in new areas, the poll shows. Fifty-seven percent also said if the referendum passes, it is likely to reduce metro Atlanta's traffic and congestion significantly.

"My clients ask, ‘How quickly can I get downtown? How quickly can I get to the airport?' And people who move from other areas always mention the traffic and they are only asking that because they know that the congestion is a problem," said Jackye Mumphrey, a Realtor in the Mableton/Smyrna area. She has lived in Cobb since 2003. "I think the rail will create jobs, and the areas around that will begin developing where they have the access points."

Much of the debate in Cobb has centered on its most expensive project, an $856 million transit line, possibly light rail, along a few possible routes from the Arts Center MARTA station in Midtown Atlanta to the Cumberland area in south Cobb. The line would eventually run to Acworth.

The proposed line would land in an area where professionals work and commute already. Proponents such as Stoner said having some sort of transit option would further the county’s economic development -- between 2000 and 2009, Cobb’s median household income rose from $58,289 to $62,893.

Joe Howard, a senior executive with Manhattan Associates -- a tech company headquartered in the Cumberland area with 1,000 local employees -- reinforced that view in August when he wrote a letter to Cobb officials saying his company was looking at sites in north Fulton with close access to MARTA. "The absence of rail," Howard wrote in part, "is one of Cobb’s greatest unfulfilled needs and puts Cobb and its businesses at an extreme disadvantage, not only in comparison to our nearest counties, but nationally as well."

Opposition groups, such as the Georgia Tea Party, have launched regionwide efforts to defeat the referendum, saying it is too expensive and unwieldy. But barely a quarter of metro voters said they support the tea party's agenda, the poll shows. Nearly 60 percent of respondents said they identified politically as either Republican or as an independent.

Staff writer Ariel Hart contributed to this article.

About the poll

The AJC/Channel 2 Action News poll was conducted Sept. 15-20 by Mason-Dixon Polling & Research Inc. of Washington, D.C., from Sept. 15-20, 2011. A total of 625 registered voters were interviewed by telephone. Voters were randomly selected and distributed across the 10-county metro Atlanta region, which will decide next year whether to authorize a sales tax to pay for transportation projects.

The margin for error is plus or minus 4 percentage points, which means that there is a 95 percent probability that the "true" figure would fall within that range if the entire population were sampled.

The margin for error is higher for any subgroup, such as gender groupings.