ATLANTA - Republican gubernatorial hopeful John Oxendine said Tuesday that as a voter he'll support a transportation funding plan signed into law this year.

But he won't commit to using the bully pulpit as governor to lobby Georgians to get behind it in a 2012 referendum.

"I'm going to have a million things on my plate," Oxendine told about 100 business leaders at a GOP candidate forum sponsored by the Metro Atlanta Chamber of Commerce. "I don't know exactly how active I will be in 2012."

His three leading opponents for the Republican nomination - Nathan Deal, Karen Handel and Eric Johnson - all said Tuesday they would use their influence as governor to lobby voters to push the measure through.

At issue is a transportation funding plan to boost funding for roads, bridges and rail in the state, particularly in traffic-clogged metro Atlanta. It will ask Georgians voting in the 2012 presidential primary to decide whether to increase the sales tax by one penny to pay for transportation projects. The plan breaks the state into regions; only those regions that approve the sales tax hike would receive the money.

Spending on transportation in Georgia has lagged well behind the state's explosive population growth and metro Atlanta suffers from some of the worst commute times in the nation. Business leaders - including some at Tuesday's forum - have complained that the region's notorious gridlock has made it difficult to recruit and keep companies.

One of the reasons Perdue pushed to have the vote on the sales tax increase in 2012 and not this year was to give leaders time to line up support from Georgians wary of tax increases,

Oxendine's tepid support stood out from that of his rivals.

"I will push for sales tax and go to the polls and vote for it," said Deal, the former congressman from Gainesville.

Handel said she would be "a champion and an advocate" for the proposal.

"I can't wait," Johnson said when asked if he would promote the plan, noting that as an architect he loves projects that involve building things.

The forum featured the four leading candidates for the Republican nomination for governor. Seven GOP candidates have qualified to run to succeed Perdue.

The Metro Atlanta Chamber of Commerce is hosting a similar panel for Democratic candidates June 29.