Langer entered the third round at The Quarry in Naples, Fla., with a four-shot lead and held it throughout the day, ending at 20-under 196, four better than Fred Funk (who also shot a 66) at minus-16.
Langer's dominating performance established a new tournament record, topping Jimmy Powell's mark of 197 from 1992.
Tied for third place were Nick Price (66) and Russ Cochran (67) at 15-under 201.
Mark Calcavecchia grabbed fifth place with a 4-under 68, ending at 14-under 202.
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