GREENVILLE -- By all accounts, recruiting Southwest Airlines and its lower prices to Greenville-Spartanburg International Airport would drive down the price of airfare and make the Upstate more attractive to convention planners and corporate headquarters.

But so far, state senators from Greenville County haven't been able to advance a key part of the recruiting effort -- incentives legislation -- over the objections of colleagues from Columbia and Florence.

Four senators from the Columbia area -- joined by Sen. Hugh Leatherman of Florence, the powerful chairman of the Finance Committee -- are using Senate rules to block the bill.

Sen. David Thomas, a Fountain Inn Republican running for Congress, said he figures the protests from the Midlands and Pee Dee, with time running out on this year's legislative session, spells doom for the bill.

He will push instead for a budget proviso that would have the same effect as the legislation, though he's not sure the financially strapped state government can afford the $15 million to establish a new grant program to enhance air service.

Lawmakers could act on the proviso today as part of debate on the budget.

Sen. Mike Fair, a Greenville Republican, said Charleston's influential delegation, including Senate President Pro Tempore Glenn McConnell, favors the incentives bill and hasn't been able to change the minds of objecting lawmakers.

"I don't know what it's going to take," Fair said.

The dispute may have ramifications for the governor's race, particularly candidates Vincent Sheheen and Andre Bauer, who both have strong ties to Midlands lawmakers blocking the bill and are courting Upstate voters as part of their bids for the Governor's Mansion.

Sheheen, a Democratic state senator from Camden, said through a spokesman that he has long been a proponent of expanded air service because of its importance in recruiting business. Sheheen hasn't examined the incentives legislation but "hopes to read it soon," Trav Robertson, his campaign manager, said earlier this week.

Bauer, the Republican lieutenant governor, is a former state senator from the Midlands and presides over the Senate as part of his duties. He also is a longtime political ally of Sen. Jake Knotts of Lexington County, one of the Midlands senators objecting to the bill. The others are Sens. John Scott, Joel Lourie and Darrell Jackson, all of Columbia.

Bauer said the dispute boils down to a "geographical issue with different areas of the state all wanting to have Southwest come to their part."

The bill would create a new grant program for enhancing air service that would be administered by the state Aeronautics Commission. The program would be authorized to borrow up to $15 million from the state insurance fund, with the money to be paid back with interest out of future property tax revenue from aircraft.

The legislation requires a 25 percent match from the local level.

The incentives legislation passed the House easily but got hung up on regional politics in the Senate.

Berkeley County's Sen. Larry Grooms, R-Bonneau, the bill's chief proponent in the Senate, has said the Midlands lawmakers have decided, "If they can't have Southwest, nobody will."