Indianapolis golf fans are going all in for this year's BMW Championship.

Organizers say ticket sales for the city's biggest men's golf tournament since the 1991 PGA Championship have already surpassed last year's total and that attendance for the four-day September tournament could approach 150,000. That would make it one of the tour's most attended non-majors this season.

"I think what it does is it shows how supportive Indianapolis can be when you have special events coming to town for our event or maybe another major somewhere down the road," said Vince Pellegrino, the Western Golf Association's vice president of tournaments. "It's certainly been impressive."

Daily tickets went on sale April 1, and fans are rushing to buy them despite not knowing who will actually play Sept. 6-9 at Crooked Stick Golf Course in suburban Indy.

The top 70 qualifiers receive invites to the third tourney in the FedEx Cup playoff. After the BMW tourney, the field is cut to 30 finalists who vie for a $10 million winner's check two weeks later in Atlanta.

Masters champion Bubba Watson and three-time Masters winner Phil Mickelson, Rory McIlroy, the world's No. 1 player, and defending BMW champ Justin Rose are each ranked in the top 10 in FedEx Cup points and are likely to qualify for the Indy tourney. Tiger Woods, at No. 11 in points, also is likely to get an invite.

And with almost five months to go before the tourney begins, the possibility of other big-name golfers earning invites and Indiana natives Bo Van Pelt and Jeff Overton potentially in the mix, organizers may have to revise their projections again.

Comparing attendance figures can be tricky, though, because many tournaments do not release that information, and even Pellegrino declined to say what the BMW Championship drew last year in suburban Chicago.

Organizers have already announced the tourney will return to Chicago in 2013 and 2015, with Denver hosting it in 2014. But Indy's response could push the city into the BMW rotation or perhaps prompt tour officials to give Indianapolis a chance to fill a hole on a future schedule.

"At the present time, we don't have any openings," PGA Tour spokesman Ty Votaw said Tuesday. "But certainly, Indy's record makes it a market that we would always be interested in at looking at if there was an open spot. A significant number of our events are signed through post-2014."

Phoenix typically has the largest announced crowds for non-majors, but Midwestern cities such as St. Louis and Minneapolis have traditionally drawn well when they make it onto the schedule. Crooked Stick has, too.

John Daly won his first major championship here in 1991, coming out of nowhere as an alternate to do it. Lauri Merten shocked everyone by finishing the 1993 U.S. Women's Open with three straight threes to win her only major title here. In 2005, the U.S. reclaimed the Solheim Cup at Crooked Stick when a then-record crowd of 103,500 showed up. And Fred Funk won the 2009 U.S. Senior Open in front of nearly 147,000 fans.

The course and atmosphere drew rave reviews each time, and PGA officials think it could happen again in September.

"Obviously, we're excited about our prospects at Crooked Stick this year," Votaw said. "When we made the decision to take it to Crooked Stick, we were all hopeful that Indiana and Indianapolis would support the event in a significant way and these results certainly confirm that hope and optimism. Indy is a great golf town whether it's the PGA Championship, whether it's the U.S. Women's Open, whether it's the Solheim Cup or the BMW, history has shown they love golf their golf at Crooked Stick."

Local officials contend Indy makes sense for economic, geographic and travel reasons, and hosting the most recent Super Bowl has also increased the city's national stature. They also believe the area golf community would support a tournament on an annual or semi-annual basis.

But so far, it's just talk.

"I know that each bid process is a little bit different in terms of the ones we're managing and the ones we're supporting. If they're looking for assistance on future bids we'd be happy to have those conversations," Indiana Sports Corp. spokesman John Dedman said. "I think there is a rotation that they're looking into and with the event in early September, and I think it would behoove everybody to take a look at it and have those conversations."