Dustin Johnson explains how even on tournaments that he didn't finish on Sunday, he still played well enough to have a chance. (1:04)

Dustin Johnson, for the first time, is favored to win the Masters.

Johnson is 11-2 at the Westgate SuperBook in Las Vegas, just ahead of Jordan Spieth and Rory McIlroy, who are each 7-1 and are the only others with single-digit odds.

Johnson won last year's U.S. Open, his first major championship, and, with a strong start to this season, has climbed to No. 1 in the World Golf Rankings. He is making his eighth appearance at the Masters, but first as the betting favorite. In previous years, oddsmakers viewed Johnson as a second-tier contender in the 20-1 range. But he finished fourth and sixth in his past two starts at Augusta National.

At the SuperBook, assistant manager Jeff Sherman said more money has been bet on Johnson to win the tournament than any other golfer. Spieth, the 2015 Masters champion, and McIlroy, who needs a win at Augusta to complete the career grand slam, are close behind Johnson in terms of money wagered.

Odds to win the Masters Player Odds Dustin Johnson 11-2 Jordan Spieth 7-1 Rory McIlroy 7-1 Jason Day 15-1 Rickie Fowler 20-1 Hideki Matsuyama 20-1 Phil Mickelson 25-1 Adam Scott 30-1 Henrik Stenson 30-1 Sergio Garcia 30-1 Justin Thomas 30-1 (Courtesy Westgate SuperBook)

Spieth has attracted the most money at William Hill's Nevada sportsbook, in part due to a $5,000 bet at 13-2 odds that would net $32,500. There have been big bets on McIlroy, too. Las Vegas sportsbook operator CG Technology reported taking a $2,000 bet on McIlroy at 19-2, and William Hill took a $1,900 bet on McIlroy at 12-1 on March 3.

Three-time champion Phil Mickelson, at around 25-1, also was generating interest. At the SuperBook, only Johnson had attracted more bets than Mickelson as of Tuesday afternoon.

Several longshots had seen action as well, including 2008 Masters champion Trevor Immelman, who now sits at 1,893rd in the world rankings and was the largest liability the SuperBook was facing as of Tuesday

"They bet him a 2,000-to-1," Sherman said with a laugh. "We took a few bets on him today. He's 1,000-to-1 now, but he's our largest liability."

The over/under on winning score opened at 281.5, 6.5-under par, at the SuperBook.