It was supposed to be a simple vote amid the work of redistricting: change the date of when voters would consider a proposed transportation tax from the July primary to November general election.

Enter the Georgia tea party and suddenly the vote was not so simple. After the tea party came out against the move, support among Republicans crumbled and the governor and legislative leaders were forced to drop the plan.

It's the latest victory for the state's burgeoning tea party movement, which has gained considerable momentum in the past year and is looking to further capitalize on its recent efforts. Outspoken and on the ground, they have been able to influence Georgia politics both as outsiders and as lawmakers working under the Gold Dome.

"It's been an amazing phenomenon to watch," said Kennesaw State University political science professor Kerwin Swint. "They're really having their weight felt this year in Georgia. The effect is a source of people that are really paying attention to issues and eager to tell legislators and candidates how they feel."

Nationally, tea party groups have been gathering steam since the 2008 presidential election, and have increasingly factored into the political process as anger has boiled over on issues including government spending and high unemployment. The movement was slower to arrive in Georgia, but has quickly caught up at the Capitol, with the arrivals of a new administration that is more responsive to the group and of several freshman legislators who were elected with tea party support.

Georgia Tea Party Patriots co-founder Julianne Thompson said citizens are more vocal and active than ever before, and their voices are being heard.

"They are standing up, many of them for the very first time, and they are saying, 'This is our state, this is our country, and we care about the future and the direction of our state,'" Thompson said. "We're organized. We're making the calls. We're sending the faxes. We're sending the emails. We're visiting the capitols in Georgia and in Washington, D.C. This is freedom in action."

Georgia Tea Party Board member Bill Hudson, of Marietta, said Georgia's new Republican majority isn't used to having their feet held to the fire.

"But that's what we're doing and we're going to raise hell when they're not doing what they should," Hudson said.

It was a flood of angry calls from tea party adherents that caused Gov. Nathan Deal and GOP legislators this spring to suddenly pull a bill that would have begun the process of creating a health exchange in Georgia under the federal health care law. The thought behind the bill was that Georgia needed to take control of the process in case the federal law survives legal challenges, but the tea party felt it would undermine Georgia's opposition. In the end, Deal formed a panel to study the exchanges and put Thompson on it.

Hudson said any doubts the tea party would be unwilling to split from the GOP should have been eliminated after the battle over tax reform earlier this year. Tea party groups aligned with Democrats at the Capitol to help defeat a proposed tax code overhaul, arguing the Republican plan would actually hike taxes on many Georgians.

Hudson said he and other tea party groups plan to hold lawmakers accountable for votes that increase taxes or spending.

"If they're not scared they ought to be," he said. "Because we'll do anything we can to get them out of there."

Their single-minded opposition to tax hikes and aversion to political compromise can irk some legislative leaders, who must deal with the reality of governing. They are, nonetheless, often unwilling to criticize the group for fear of falling out of favor.

House Speaker David Ralston downplayed the tea party's role in sinking the transportation measure.

"I think the Republican caucus in the House thinks for themselves," Ralston said. "We listen to a lot of groups here."

To be sure, counties also opposed moving the date of the transportation referendum, which had an effect on the outcome.

Lt. Gov. Casey Cagle stopped short of calling the transportation tax a victory for the tea party, but agreed they are having an impact on the state's politics.

"I think all constituencies that bind together have a voice," Cagle said. "This is what democracy is all about. They clearly weighed in very heavily, but (they were) not the deciding factor."

Senate Rules Chairman Don Balfour, R-Snellville, said the tea party opposition was "very influential" in the outcome of the transportation fight.

"Legislators want to hear from their constituents, and they're being heard," Balfour said. "They weren't being heard because they weren't speaking up. Now, they're frustrated with the federal government, and that's trickling down to all government."