Just when you thought you had the next governor’s race all figured out, Lt. Gov. Casey Cagle decides to mess everything up.

 Cagle had been the early frontrunner for governor and was still considered the man to beat, even after he failed to broker a deal in the General Assembly for a transportation funding tax. He consistently ran ahead of the other Republican hopefuls in the early polls and he would have been favored over the Democratic nominee.

 Nothing in life or politics ever works out quite that neatly, however, and so it was with Cagle. He abruptly announced last week that because of "back problems" he was dropping out of the governor’s race, although insisting he would still run for another term as lieutenant governor.

 The Cagle pullout probably ensures that former governor Roy Barnes, who still hasn’t made a public announcement of his plans, will finalize his intentions to run again. More importantly, Barnes could get a monetary boost from business leaders fed up with the Republicans’ inability to pass a transportation funding mechanism — they could see Barnes as the best bet for getting something done, even if he does happen to be a Democrat.

 Cagle’s departure also leaves room for at least two or three additional candidates in the GOP primary. The leading names under discussion are Cobb County Commission Chairman Sam Olens, House Speaker Pro Tem Mark Burkhalter, state Sen. Eric Johnson (who’s running for lieutenant governor but could easily switch races) and members of the state’s congressional delegation (Lynn Westmoreland or Jack Kingston).

 It will be a big field of candidates, each of them with their own vulnerabilities that leave them open to attack.

 Barnes has been traveling around the state to talk up his candidacy and he is being told by party activists that they won’t support him unless he cuts his ties with political mastermind Bobby Kahn, who is blamed for the 2002 loss to Sonny Perdue and the subsequent collapse of the Georgia Democratic Party. Would Barnes actually do such a thing? More importantly, would Bobby allow him to do it?

 Attorney General Thurbert Baker would be considered the most serious challenger to Barnes in the Democratic primary, but after 12 years in office it would be difficult for the average voter to tell you who Baker is or what he ever accomplished. Baker rarely took a stand on anything, which doesn’t leave him with much of a platform to run on.

 Insurance Commissioner John Oxendine becomes, for the moment, the poll leader on the Republican side, but the man they call "The Ox" will have to spend a lot of time explaining to voters why he wrecked so many state vehicles and why the attorney general’s office forced him to turn off his "blue light."

 Secretary of State Karen Handel is the GOP candidate with the backing of Gov. Sonny Perdue, who sees her as the best choice to continue the "accomplishments," such as they are, of his administration. Handel has devoted most of her energies as the state’s chief elections officer to pushing for legislation that makes it more difficult for blacks and Latinos to vote. That won’t do her much good now that the U.S. Justice Department is controlled by Democrats who frown upon such voter suppression techniques — and have the authority under the Voting Rights Act to do something about it.

 Sam Olens is probably the most intelligent, best-qualified candidate of anyone running in the Republican primary, but he has a couple of handicaps that will hurt him among GOP voters. He holds three college degrees and is also a Jewish candidate in a party dominated by its anti-intellectual, Christian-right voting base. Olens is running in the wrong state with the wrong party.

 Rep. Austin Scott (R-Tifton) has a similar problem to Olens. He has displayed an admirable independent streak during his years in the state House, supporting the new state flag in 2001 and expressing sympathy for the problems faced by Georgia’s immigrant community. Those political stands would be okay if he were running in the Democratic primary — but he’s a Republican.

 There will be a lot of people who qualify for the governor’s race next year — but nobody is a guaranteed winner. That ensures it will be one of the craziest, most wide-open campaigns we’ve ever seen.