Fleisher entered the final round with a four-stroke lead, maintained the advantage through the first nine holes and then turned it into a rout with three straight birdies over the final six holes.
D.A. Weibring and Bruce Lietzke tied for second at 9 under. Defending champion Tom Jenkins fell from second to fourth after a double bogey on the final hole, when his tee shot hit a cart path and bounced out of bounds.
The previous biggest margin of victory at Bruno's was five strokes by Graham Marsh in 1995.
Fleisher is just the second player in tournament history to lead wire-to-wire, joining Hale Irwin, who was tied for the lead after the first round in 2001.
'He just obliterated the rest of us,' said Irwin, who fell out of contention with a final-round 75.
Weibring was the only player to make a run at Fleisher, albeit briefly. He cut the lead to two strokes with a 12-foot birdie putt at No. 4. Fleisher birdied the next hole, Weibring sent his tee shot off a tree and into the woods, making a bogey at No. 8, and the lead was back to four.
'Bruce played a terrific, real solid round and made a couple more putts to put it away on the back 9,' Weibring said
Fleisher also had birdies at Nos. 13-15, breaking a string of seven straight pars while Weibring made bogey at No. 11 and Jenkins had a bogey at the 10th.
'He didn't make many mistakes, and D.A. and I didn't really put any pressure on,' Jenkins said. 'He was on his game. He wasn't going to make any mistakes.'
It was the 18th career victory, and second of the year for Fleisher, who won the Royal Caribbean Classic in February. The last time he won two tournaments in a season was in 2001.
Lietzke had five birdies over the final nine holes and finished with a 67.
The final round started in the early afternoon, allowing the course to dry after overnight rains.
DIVOTS:@ With 13 different winners in 13 years, Bruno's has the longest run on the Champions Tour without a two-time winner ... Fleisher is the tour's first multiple winner after nine events.
Copyright 2003 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.