The Englishman is just two shots behind the leader Ben Crane and is in a tie for third with six other players in Florida.
The Ryder Cup star was in superb form and six birdies saw him rise to the top of the leaderboard during his opening round.
But he had to settle for a share of third place after the opening 18 holes after Crane shot 65 and Germany's Alex Cejka, Sweden's Richard Johnson and American John Mallinger went round in 66 shots.
Tiger Woods shot 71, Padraig Harrington 72, while Phil Mickelson was one-over par on 73 going into the second round.
Poulter's putter was hot and he took just 26 putts on Thursday, something he pouts down to a change of club in recent weeks.
"I changed to a putter two weeks ago that the ball comes off a bit slower and the greens have been very quick the past couple of weeks and I just feel good," he said.
"I've played one week on, one week off until just after the Masters, so it's been hard to get into a routine.
"But my game's been in shape since then and I felt it was only a matter of time."