Tuesday’s vote on a regional transportation sales tax is a big deal.

It would raise taxes by 1 percent on a big portion of purchases, including food. It would have a bigger lifespan than county-level sales taxes, staying in place for a decade. And it would raise big money, estimated at about $748 million in Middle Georgia, that would be paired with state and federal funds to build about $1.2 billion in transportation projects.

The tax -- known as the transportation special purpose local option sales tax, or T-SPLOST -- is also attracting big support and big opposition.

The list of major T-SPLOST projects was reviewed by a group of 11 midstate county commission chairmen and 11 mayors, who united in support behind it. Big businesses have signed on to support T-SPLOST, but opposition is coming from a variety of sources, including tea party groups, the NAACP and a group led by former Houston County Commission Chairman Ned Sanders, who argues the regional tax would undercut his county’s efforts to upgrade its own roads.

At 76 projects -- some of which are just parts of bigger projects -- there’s a lot to take in. And the projects are scattered across an 11-county region that runs from Putnam County to Pulaski County, a swatch that also includes Baldwin, Bibb, Crawford, Houston, Jones, Monroe, Peach, Twiggs and Wilkinson counties.

That project list is expected to consume about $561.6 million of the T-SPLOST money, which would be matched against about $514 million in state and federal money if the T-SPLOST is approved.

The project list would claim three-quarters of the T-SPLOST money. The remaining money, about $187 million, would go to local governments for their own transportation uses, such as regular road paving.

The T-SPLOST is polarizing and, at times, confusing. The Telegraph asked more than a dozen Macon and Bibb County elected officials a month ago how they’d vote on the T-SPLOST, and most then hadn’t made up their minds.

Byron Mayor Larry Collins, who helped represent Peach County in the regional roundtable that developed Middle Georgia’s project list, said he and every other county in the discussions honed in on projects that would support Robins Air Force Base -- and, essentially, Houston County.

Still, since the project list was approved, Houston County commissioners have all publicly said they do not support the sales tax because Houston County would provide more toward the T-SPLOST than it takes in.

Collins said he understands the reasoning among Houston County officials but still supports the T-SPLOST as a whole.

“They have the income and the ability to do without the T-SPLOST. We don’t,” Collins said. “Houston County can do their own road projects, but the rest of the counties can’t.”

But Sanders, former chairman of the Houston County Commission and current chairman of Citizens Against T-SPLOST, said it’s not that simple.

“There’s still billions of dollars coming in to do roadwork,” he said. “It’s just some of the projects wouldn’t get done as soon, and probably some of them should never be done.”

Sanders’ concern is that if T-SPLOST passes and is in effect for at least a decade, it will hurt counties’ abilities to renew badly needed sales taxes for operations, county capital improvements and education improvements.

“It poisons the water,” Sanders said.

Telegraph readers had their own questions about T-SPLOST that simply don’t have answers. Robert Danner of Macon wanted to know how much of the sales-tax collections would come from inside the region, while Bob Nickels of south Bibb County wanted to know exactly what the unemployment rate would become if T-SPLOST was passed.

Laura Mathis, deputy director of the Middle Georgia Regional Commission, said no studies have been conducted to answer those questions.

Greg George, director of Macon State College’s Center for Economic Analysis, said he hadn’t studied the T-SPLOST’s economic impacts. He said, however, that T-SPLOST might be good for the economy.

“Infrastructure costs are usually well-spent money,” he said.

But George said money someone spends in sales taxes in one weekend can’t be spent the next at a local restaurant, something economists call an opportunity cost. But if the transportation projects ultimately will be built even if T-SPLOST fails, the sales-tax money isn’t truly diverted from the economy.

“If you’re really going to have to pay for it anyway, that means the opportunity cost goes away,” he said.

And the kind of transportation project also matters. Many infrastructure projects bring long-lasting economic benefits. Wasteful projects like “bridges to nowhere” generate few long-term jobs and have maintenance costs, George said.

Other readers had fundamental economic questions. “Is it 1 cent or 1 percent?” asked Betty Dalacos of Gordon.

If approved, the T-SPLOST would add 1 percent to the cost of most items. If someone buys $200 worth of clothing, they will pay an extra $2 in sales tax. In most Middle Georgia communities, the sales-tax rate would rise from 7 percent to 8 percent on most purchases.

The T-SPLOST would have some unusual exemptions and applications. For example, food would be subject to the tax, but gas wouldn’t. The first $5,000 of a car purchase would be taxed, with the maximum T-SPLOST tax on a new car capped at $50.

Reader Tom Saul of Perry wanted to know what would happen if some regions of the state approved the tax and others didn’t. Mathis said the taxes are determined by a majority of taxpayers across each region. If Middle Georgia votes one way and the Atlanta area votes the other, one region would have the tax and the other wouldn’t. Likewise, some counties may vote against T-SPLOST but the overall region approves it. If that happens, the tax is in effect for everyone in the region, including the counties that didn’t pass it.

Money raised in the region is to be used in each region. Mathis said the only exception is administrative fees paid to the Georgia Department of Transportation, which would only cover costs in each region.

Telegraph reader Mary Katz wanted to know if sidewalks would be included when Bass Road and other Bibb County roads are widened, and whether any bike lanes were planned.

Mathis said Bibb County’s standard design includes sidewalks. Bibb County’s planned projects include bicycle and pedestrian lanes on Pierce Avenue, Riverside Drive, Rivoli Drive and Wimbish Road.

Katz said she wanted guarantees from the Georgia Department of Transportation.

“Unless it’s nailed down as a requirement, I don’t trust the DOT to do it,” she wrote in an e-mail to The Telegraph.

Information from Telegraph archives was used in this report.