Bluhm, who owns casinos in Pennsylvania, Chicago and Niagara Falls, has a net worth of $2.6 billion, according to Forbes. The former lawyer and now head of Rush Gaming believes Osaka, one of Chicago's 'sister cities', has the kind of flexible local government that will help drive this project, and, crucially, has "shovel ready" casino sites.
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He says the whole process - from approval to construction - in Tokyo will be more complex, more time-consuming, and more expensive.
While Adelson hasn't ruled out pitching for Osaka, too, he sees Tokyo as the main prize, given its highly affluent 13.2 million population. The CEO of Las Vegas Sands Corp, who Forbes says is worth close to $39 billion, has pledged to spend $10 billion as Japan opens up to legal gambling - an offer he says his rivals can't match.
Throwing big numbers
In a recent report, Morgan Stanley predicted that a Japanese casino resort costing more than $5 billion would offer a return on investment of below 20 percent due to rising costs and a struggle to attract enough high-rolling Chinese VIP customers.
Sands, which has casinos in Macau, Singapore and Las Vegas, remains bullish on its Japan plans given the country's wealthy population and proximity to China. "We are very confident in our ability to generate a return that would be satisfactory to our shareholders," George Tanasijevich, managing director for global development, said in a phone interview. He did not elaborate.
Bluhm shrugs off rivals' talk of big money spending.
"Sometimes people like to throw big numbers around in order to get picked ... We have been more for Osaka in the $4-$5 billion range," he told Reuters.
Bluhm also reckons he may have an edge over the big operators in Macau - who he thinks likely prefer Tokyo - by working alongside local partners. "In reality, they are going to want to totally run the project. They are probably not used to having partnership relationships like we are," he said.
Osaka's government is keen for foreign operators to use Japanese firms in a consortium or joint venture, said Masayuki Inoue, director general of the city's economic strategy bureau, stressing Osaka wants a large casino resort with convention and entertainment facilities. "Osaka city is flexible. We're ready to discuss anything."
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The Kansai Keizai Doyukai, a leading local business lobby, reckons land costs in Osaka will be a tenth of those in the capital, some 250 kms (155 miles) to the northeast. And, it says, the city can offer a development area three times bigger than that occupied by Singapore's two casino resorts - Marina Bay Sands and Resorts World Sentosa.
Fifty-six percent of Osaka residents polled in April said they were positive about the city of 2.8 million people having a casino resort. The city, located on Honshu island at the mouth of the Yodo River has a reputation for being more extrovert than Tokyo, and local authorities have designated a 170-acre plot of reclaimed land, known as Yumeshima, as the preferred resort site.
Osaka's Governor Ichiro Matsui told Reuters last month that casino operators would invest around $5 billion for an integrated resort, and bear some of the infrastructure costs such as a potential rail link.
In comparison, officials in Tokyo, already setting about preparing for the 2020 Olympics, appear more tortoise than hare.
Industry executives worry privately that Tokyo is so focused on getting the Olympics right that there's little momentum driving the casino issue. Tokyo Governor Yoichi Masuzoe, a former health minister, has yet to say whether he will seek a casino license for the capital or not.
"We're not like Osaka and Yokohama. We haven't stepped on the accelerator and said let's go," Yukimasa Saito, an official at the governor's office, told Reuters.
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A waterfront area called Odaiba in Tokyo Bay has been touted by executives and officials as a preferred location for any casino resort in the capital, but securing enough land could prove a challenge.
At present, around 14 hectares (34.6 acres) are available for sale by the city behind the headquarters of TV broadcaster Fuji Media Holdings. Doubling that would require re-zoning parks and buying land currently owned by a real estate developer and Toyota Motor Corp, said an official in Tokyo's waterfront development division.
The department sparked concern among some casino watchers about Tokyo's intentions last month when it said it would auction a 2.7-hectare plot in the Odaiba area for a 10-year lease - effectively taking the lot out of the equation for casino resort developers.
In Osaka, officials say a casino would help spur Japan's tourism beyond heavily populated Tokyo. Osaka is just half an hour from the former imperial capital Kyoto and trade hub Kobe.
Other regional hubs, such as Sasebo in the south and the ageing port city of Otaru, have also said they would welcome casino plans to boost tourism. None are as far advanced in the process as Osaka - where a common local greeting is "mokari makka?" - are you making money?
While rival operators - including Melco Crown Entertainment, MGM Resorts International and Genting Singapore - are eyeing both Tokyo and Osaka, Bluhm says he's already in talks with Osaka-based Japanese companies across a range of industries.
For residents like Yusuke Sawada, a 30-year-old architect, a casino resort could be a boost for local Osaka businesses.
"If casinos come, it can bring more tourists to spend big money. Osaka has much less money (than Tokyo). We need it more."