Georgia's GOP Senate primary to replace retiring Sen. Saxby Chambliss remains anyone's game, according to a new poll from Georgia-based Landmark/Rosetta Stone.

No Georgia Republican cracks 20 percent in what is expected to be a crowded field. Lt. Gov. Casey Cagle leads with 17 percent. Reps. Phil Gingrey, Jack Kingston, Tom Price and Paul Broun all receive between 10 percent and 15 percent of the vote. One-third of voters are undecided.

Broun is the only candidate officially in the race at this point, though sources tell The Hill that Gingrey has told Georgia Republicans he's definitely running. Kingston also appears likely to make a bid, while Price has said he'll wait until May to make a final decision on the race. Cagle seems the least likely to make a run for the seat.

The automated survey of 483 likely GOP primary voters has a 4.5 percentage point margin of error.