The American duo went round in 12 under on Saturday in the fourballs and went two better in the final round scramble to finish seven shots clear of Retief Goosen and Freddie Jacobson.
Goosen and Jacobson fired 11 under for the second day running but that was only good enough to put them 27 under for the tournament and left them trailing in the wake of Harris and Kuchar.
European Ryder Cup duo Lee Westwood and Ian Poulter were a further shot back after firing 59 on Sunday with Chris DiMarco and Billy Horschel a shot behind them.
Defending champions Sean O'Hair and Kenny Perry held the lead after day one but lost ground in Saturday's fourballs and finished the tournament on 23 under.
Rory Sabbatini and Scott Verplank finished on 22 under with Charles Howell and Justin Leonard a further stroke behind.
There then came a group of three teams tied for eighth with tournament host Greg Norman and Jonas Blixt, Jerry Kelly and Steve Stricker, and Graham DeLaet and Mike Weir all on 19 under.
Jason Dufner and Chad Campbell finished a further shot back with the pairing of Chad Campbell and Mike Calcavecchia completing the field on 15 under.