2013 was a winning year for the big casino players -- especially Las Vegas Sands (LVS -0.36%) and Wynn Resorts (WYNN -1.72%). Both companies benefited greatly from the continued outsize growth in Macau, new Asian gambling prospects, and even some good numbers back home. Even though the industry tailwinds were well documented, the market underestimated both companies last week when they reported their respective earnings, giving the stocks an even greater boost on top of their huge gains last year. With so much good news, it's hard to look away from either -- but which is the best for your investment dollars?

Recent trends
Late last week, Las Vegas Sands reported a bottom line that grew 32% to $0.70 per share while Wynn delivered an adjusted $2.27 per share -- more than $0.50 ahead of analyst estimates. Both companies saw the bulk of their growth from Macau, China's only legal gambling region and the champion of casino growth in recent years. Wynn's Macau operations grew sales by 25%, while Las Vegas Sands posted 28%.

Both companies are spending billions on new resorts on the Cotai Strip, Macau's equivalent of Vegas' main drag. On the earnings call, Wynn's namesake and founder, Steve Wynn, noted that the company was on track to finish its newest $4 billion megaresort, the Wynn Palace, by the beginning of 2016. Then, we learned more about what lies ahead for the Palace: Two years following its completion, Wynn will embark on a second development phase -- adding another 1,500 rooms with ridiculous features such as 80-inch TVs in every room of the all-suite hotel. The total bill for the Wynn Palace could hit $9 billion.

The company's first hotel on Macau, the Wynn Encore, generated $1.3 billion in sales last year. When it was built (coming up on one decade ago), it cost the company $1.5 billion. It's the only Macau hotel to receive 5-star ratings across the board.

Las Vegas Sands is a bigger company, especially back in Vegas, where it has more rooms, more machines, more tables, and much bigger sales, led by its flagship, the Venetian. The company has three properties in Macau, and by taking a mass-marketing approach to its business can make a buck faster than its competitor. Investors and analysts like the prospects of mass-market gambling, which is growing faster in Macau than the gambling market in general. Margins are higher and the volume is less volatile, compared to VIP gaming. Even with its tremendous growth, Macau is still building a base in its popularity with mainland Chinese. As the Chinese middle class grows and learns of the wonders that happen on the island, mass-market gaming should only increase, bringing Las Vegas Sands' financials with it.

An opening market
While Macau is the big driver for both Las Vegas Sands and Wynn Resorts, there are multiple prospects on the horizon that should keep both companies flush with growth for years to come. For one, the Japanese gambling market appears to be opening up. The laws have allowed for gambling on races for some time, but slot machines and tables were never part of the deal. As Japanese regulators open up the country to comprehensive gambling, both companies are preparing multibillion-dollar introductions.

According to UBS and Citibank, it looks like if all were to go well, Las Vegas Sands would again be the first to market on the island nation. The advantage likely goes to Sands because of its proven ability to jump-start tourism in Asia. As noted by fellow Fool Jayson Derrick, Sands' Sheldon Adelson took credit for bumping up Singapore's tourism numbers by 41% upon the opening of its resorts in the area.

By the end of the decade (or shortly thereafter), Japan could become the No. 2 gambling market, under Macau. If it's awarded the first license to play ball, Las Vegas Sands will have a leg up, at least for a while.

In part deux...
With new markets on the horizon and the golden anchor that is Macau leading both companies into 2014, it's hard to imagine either as a sour bet. Still, one of these businesses has something the other doesn't. In part two, we'll look at the state of things back in the U.S., and then on to choose a winner.

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