Poulter had three birdies and the eagle in the final round to go with a 17th-hole bogey for a 4-under-par 67 and a 72-hole total of 15-under-par 269.
No other golfer was within eight strokes of Poulter.
Poulter opened Sunday's final round two strokes behind Ogilvy but wiped that out when his 5-wood tee shot on the 255-yard first hole ended up within 20 feet of the pin. He made the eagle putt while Ogilvy had a par on the hole.
Ogilvy, who eagled the first hole Saturday, opened his Sunday round with 12 consecutive pars before bogeys at 13 and 15. He managed a birdie at the 16th hole but had a double bogey 7 at No. 17 that a final-hole birdie couldn't offset.
Poulter and Ogilvy were tied through six holes but Poulter pulled away with birdies at 7 and 9. He matched Ogilvy's birdie at 16 and, even after a bogey at 17, was up five going into the final hole.
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