Gentlemen, place your bets.

Well, before you do, someone else has to place your odds. With this Sunday's Kobalt Tools 400 to be run at Las Vegas Motor Speedway, did you ever wonder who sets all those odds everyone scrambles to bet on? Better yet, did you really have any idea how many different "proposition bets" you can legally lay down on NASCAR races every week in Vegas?

Three such gentlemen explained how they go about their business so visitors to Vegas for this weekend's Nationwide Series and Sprint Cup Series can go about their betting in sports books all over town.

Micah Roberts, who has spent 18 years setting odds on NASCAR events for the old Circus Circus, Station Casinos and now, said it is a mostly a matter of studying some history and some numbers. Lots of numbers.

"Basically how [odds are] set is you set it up by tendencies, by how drivers have done in the past at particular track or a particular track style," Roberts said. "Like Las Vegas, for instance, we can go back maybe not the whole year at mile-and-a-half, high-banked tracks -- but we can go back to the end of last year's Charlotte race, Atlanta, Homestead and kind of mix in the most recent tracks and see how the drivers did.

"For instance, Kevin Harvick is not the favorite this week. But he was so good on all those tracks last year, even at the beginning of the year. Out of eight races total last year, including Chicago and Kansas, I think he finished in the top 11 in [eight of 10] of them. nobody else was close to him. Not even Jimmie, even though Jimmie won one of those races."

So even though Harvick is not the favorite according to the odds, he would be a good pick this weekend according to Roberts. Roberts lists his top five for this weekend as Johnson (9-2), Carl Edwards (5-1), Kyle Busch (6-1), Denny Hamlin (8-1) and Jeff Gordon (10-1). He lists Harvick, last year's runner-up to winner Kurt Busch, at 12-1

"Johnson is the favorite because he's been so consistently good and he's won here four times, twice before the track was reconfigured and twice after," Roberts said. "Then also, later in the year, you're looking at a driver's ability to win. Kyle Busch obviously wins at a higher rate than he finishes well -- and that's why he can't win a championship. But when he has a chance to win, he usually does. It's very rare to see him bullied out of the way like Gordon did [last Sunday] in Phoenix.

"So that figures into it, too -- the driver's tenacity and ability to close out a race. Johnson, Busch and Hamlin have that, so those guys are always going to be the favorites at tracks like this -- and then you mix in a little bit of what they've done recently, how the team is flowing a little bit, how the team is gelling, and you put all of that into play."

Oddsmakers also like to put into play what they call "proposition bets," which are very popular amongst both professional bettors and the novice betting public -- depending on whose setting them and why. Ed Salmons runs the sports book at the Las Vegas Hilton and admitted his proposition bets run more to the liking of the professional gambler; Jay Rood, director of race and sports book operations for the MGM Resorts empire that includes 10 Vegas hotels and two in Reno, said he tries to gear his more toward the amateur bettor.

A proposition bet is one out of the ordinary, and the Vegas books offer quite a few. Driver vs. driver matchups are very popular, but bets can be placed each week on everything from an over-under bet on the number of cautions during a race to how certain manufacturers' cars may perform against another manufacturer to an over-under on the winning car number. Folks also can wager on who wins the pole and "just about anything that can be verified and validated through the final box score" of a race, according to Roberts.

Salmons said he tries to keep his driver matchups simple and straightforward, because he knows he is setting lines that will be scrutinized -- and bet against -- by mostly professional gamblers.

"I would say 90 percent of the money you write on the matchups are professional bettors," Salmons said. "Other than this week, if you go around Las Vegas, you're not going to see a lot of matchups at sports books -- because they're just afraid to book 'em because they know they'll lose on 'em. I'll tell you right now, booking NASCAR matchups is one of the hardest things to do as far as what we do here. It's just a hard thing to beat.

"We usually put out 17 matchups for a race. This weekend, we'll definitely do more because the race is in town. We have to put a price on every matchup, and they can pick and choose whichever ones they want. Just like in college basketball; when you have 112 games, they only have to pick the ones they like. The guys who do this for a living are really good. You're going against the best of the best in this stuff, and they're pretty good at what they do. I'd like to think I'm pretty good at what I do, but I also know there are a lot of people out there smarter than I am."

Rood said he takes a different approach when setting the lines and nature of the NASCAR bets for MGM Resorts.

"Being a big network operation, we tend to cater to the public, the people who are staying at our hotels, rather than the professionals for these particular events," Rood said.

While he said the betting pros "look for the straight statistical angle," the novices like for it to be kept simple. And he agreed with Salmons that the general public definitely likes to "bet a little in the hopes of winning a lot." That means they tend to bet on longer shots where the odds are greatly against them -- and in favor of the casinos raking in their money.

"Driver matchups are pretty popular, and then we do best finish where you take smaller groups and knock it down to the best finish, where we do four drivers in each group. And they tend to like that, because with the public you're usually taking plus-money on every driver in that situation," Rood said. "Whereas if you just have head-to-head -- say (Matt) Kenseth vs. [Dale Earnhardt] Jr. -- Kenseth would probably be a $1.50 favorite in that matchup, so that means you'd have to lay Kenseth $1.50 and Junior you would take plus-$1.30 -- but if you throw in a third driver, Kenseth's odds come down to even-money or possibly even 6-5, depending on who the other driver is.

"The general public tends to not want to lay odds. They like betting lower amounts to win higher amounts, so if you can give them 6-5 or 2-1 [odds] or whatever, they're more inclined to get involved in those types of propositions than the other way."

Confused yet? Let Rood break it down a little further, as he did several years ago for MGM.

"We started with the matchups and we were trying to tinker with them to make them more like what they see on the board with other sports, like football and basketball, where you put up a matchup and you handicap it -- and instead of them laying like $1.50, you lay positions," he said. 'So you would put up Kenseth vs. Earnhardt Jr., and Kenseth might be a 3½ position favorite -- meaning that he would have to finish four positions in front to beat Earnhardt and you would lay $11 to win $10, just like you do in other sports. We're probably going to have a few of those up on the board this year as well.

"There's not such a big outlay of money. If they want to win $20, they know they've got to bet $22 to win $20 just like they do in football or basketball. Whereas the other way [if they bet Kenseth laying off $1.50] they have to bet $30 to win $20."

Salmons said while the proposition bets are popular, the simplest bets of all are the ones where cash is bet on who will win the race.

"The odds-to-win are very popular. Because anyone can look at it and say, 'Well, who's going to win the race?' And then they can bet a little and win a lot. So that's why they like to bet the odds-to-win," Salmons said.

"Like [last Sunday], we had Jeff Gordon at 20-1 to win that race. He was starting pretty far back on a track where it's hard to pass, but things went his way in that race. He obviously was the best car toward the end of the race -- and 20-1 is a real nice price. He hadn't won in almost two years, but someone won some money on him [Sunday]."

Roberts, Salmons and Rood said everything possible is taken into account when setting odds for a race. But all three sheepishly admitted Daytona 500 winner Trevor Bayne's name was nowhere to be seen on any of their pre-race betting boards prior to his huge upset.

"That's a funny story," Salmons said. "I put my Daytona 500 odds up, I think it was the first week of December, somewhere around there. I remembered that he had run a race in that car [previously] but I didn't think he was actually going to run in it for the 500. Because if I had realized that, I would have listed him. So he was in the field. I think we listed 29 drivers in the field -- and we always will get people who will bet the field. On a restrictor-plate track, our field price usually is about 30-1. For the Vegas race, it'll probably start at 100-1 and finish at more like 200-1 -- because most of those guys have no chance to win. In a restrictor-plate race, obviously anyone can win one of those things.

"So a lot of people bet that [the field at Daytona], and it was a losing proposition for us. But the reaction in this sports book was just amazing at the end of that race. People were just cheering and jumping up, like it was one of the bigger football games."

Rood said he didn't have Bayne on his Daytona board, either. He did have David Gilliland, who finished third, listed at 200-1; and Bobby Labonte, who finished fourth, listed at 300-1.

"If Bayne had made the list, he probably would have been between 200-1 and 300-1," Rood admitted.

But that race weekend is in the past. Now it's time to take the bets for the next one. All Roberts knows for sure is that it's going to be a very busy weekend in that regard.

"Vegas is always the No. 1 bet event of the year, just because of all the foot traffic through the casinos," Roberts said. "That's a targeted audience and they love it. Then second would be Daytona and third would go to maybe the Coca-Cola 600 or the Brickyard. Talladega is always a popular event as well.

"There are only 36 [Cup points] races, so when you're comparing only 36 events to the other sports, you're comparing apples to oranges. In the NBA, each team has 82 games and they have 30 teams. You multiply that over the long haul and there's no way NASCAR as far as the weekly handle could collectively compare to that. But as one event, you put that one event against any one basketball game over the weekend and it will be the most bet-upon event of the weekend. Even a big college basketball game, there won't be anything that comes close to what that one event does for NASCAR. And that's on a weekly basis.