Four bidders. Three cities. Two spots.

With long-shot Las Vegas now out of the running, the race to join MLS in time for the 2020 season became a lot clearer this week, as the league said “thanks, but no thanks,” to Sin City.

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While collective bargaining negotiations with the MLS Players Union remain the priority – there’s still no guarantee the 2015 campaign will start as scheduled on March 6 – the expansion conversation continues in the background. And it surely will heat up once labor peace is achieved. MLS has said it intends to make its decision by June, although there are indications that news could come significantly sooner.

The dynamic is relatively straightforward.

MLS wants to be in Minneapolis, which anchors the 15th-largest media market in the U.S. Only four metropolitan areas host a greater number of Fortune 500 companies. Those statistics, plus the Midwestern location and the presence of two well-funded ownership groups, make the Twin Cities an attractive and obvious option.

The Minnesota Vikings' bid resembles that of Arthur Blank and the Atlanta Falcons, who were awarded an expansion team scheduled to kick off in a new NFL stadium in 2017. (Atlanta already has taken 17,000 season ticket deposits). The Vikings don’t have roots in the local soccer market. But they do have a billion-dollar stadium under construction.

It's designed to be fitted with a downsizing mechanism featuring “a stylistic curtain system with soccer specific logos and décor.” The building, which would seat 25,000 for soccer, is scheduled to open in July 2016. The Vikings also possess the pro football cache that might appeal to an MLS board that includes four additional NFL owners.

Minnesota United bolsters potential MLS bid with Twins, T-Wolves backing

Minnesota United, which currently plays in the North American Soccer League, has stayed quiet regarding its MLS ambition while putting together a formidable investor group that includes the owners of the Minnesota Twins and Timberwolves. For United, which can trace its lineage back to 1990, moving to MLS may be the only way to ensure survival. Its success depends on whether it can guarantee the construction of a new, soccer-specific stadium in downtown Minneapolis.

United, led by majority owner Bill McGuire, is eyeing a piece of property on the northwest edge of downtown between Target Field, the home of the Twins, and the Minneapolis Farmers Market. The only unresolved element is the extent of a potential public-private partnership between United and Hennepin County. United’s owners have an architect signed up and the money to start building. As discussions with the county continue, the stadium project should come into further focus.

Considering the likelihood of an MLS franchise in Minneapolis and the desire of both United and the Vikings to start construction and planning, a league decision may come in April or May. MLS very well could award team No. 23 before confronting the challenge of No. 24.

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That race is between the fantasy and the sure thing. The prospect of a David Beckham-owned team in Miami sounds glamorous. The retired English midfielder exercised an option to buy into MLS at a reduced rate he secured when he signed with the LA Galaxy back in 2007. If Beckham could attractinvestors and guarantee a stadium, he’d have his team. But that’s proven easier said than done.

A pair of proposals focused on the Miami waterfront fell flat and Beckham, perhaps feeling a bit burned by the ensuing negative publicity, has opted to stay vague when discussing the expansion effort.

“We're making some really good progress, some real positive progress, so at some point in the next couple of months there will be some announcements,” and “We're pretty close to announcing certain things and then the stadium will come after that,” are two recent offerings.

There’s been speculation that members of the MLS board of governors are concerned with the lack of progress. Questions have been raised about whether Beckham and his colleagues, manager Simon Fuller and telecommunications executive Marcelo Claure, can guarantee the requisite funding. But a source said that Beckham actually has several options in the Miami area and simply is working on selecting the best piece of property. If faced with a deadline, he could pick a site and start building.

Beckham and Fuller met with MLS commissioner Don Garber this month in Los Angeles. Pushing a decision on team No. 24 into June would give Beckham more time to figure it all out. Meanwhile, Sacramento waits.

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Sacramento Republic, which attracted record crowds and won the USL Pro championship last season (its first), theoretically could start playing in MLS as early as 2016. Bonney Field could be expanded to around 14,000 seats while the club’s proposed $150 million stadium at the Sacramento Railyards is built. The most pressing issue with Republic’s bid, a potential rivalry with the NBA’s Kings, was resolved late last month when the basketball team bought in. Then the owners of the San Francisco 49ers invested as well.

MLS couldn’t have anticipated Sacramento’s progress when it laid out its 24-by-2020 plan in 2013. Now, it faces a potential PR problem. Sacramento has met every bit of the league’s expansion criteria, both theoretical (well-funded ownership group, proven market, downtown stadium, etc.) and specific (starting with the Kings partnership).

If Republic is given the green light this year but told to wait until 2018 -2020 to enter the league, the San Jose Earthquakes would have ample time to establish traction at new Avaya Stadium. The Quakes’ concerns about territorial integrity and the possibility that Republic might eat into its base of corporate support should be alleviated by that time. The knowledge that an MLS rival two-plus hours to the northeast likely precludes one from eventually setting up in San Francisco also might appeal.

In other words, it’s getting tougher for MLS to justify saying ‘No’ to Sacramento, which is the country’s 20th-largest market. But the league is on the hook with Beckham as long as he furnishes an adequate stadium. Whether he can do so by this summer likely will determine Sacramento’s immediate expansion fate.

It’s noteworthy that Garber, in his letter to Las Vegas mayor Carolyn Goodman, wrote, “We are no longer considering Las Vegas as an expansion market until after 2018.”

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It’s there in black-and-white. Once Atlanta, Los Angeles FC, the winner of the Minneapolis derby and either Miami or Sacramento are identified and on their way to filling out the league’s quota of 24 in 2020, expansion may once again become an issue.

No one believes MLS intends to stop definitively at 24 clubs, even though it doesn’t currently have a plan in place to go beyond that number.

St. Louis, San Antonio and Austin are among the interested markets, and Indianapolis could enter the picture if a new stadium proposed for the NASL’s Indy Eleven is built.

If Sacramento is the odd team out this year, it likely won’t be permanently. If Beckham is able to build and Republic is able to maintain its hold on its investor group and stadium site, it would have an ironclad claim on slot No. 25. And if Miami (or LAFC) falters, California’s capital will be waiting in the wings.