Super Bowl LII will bring more visitors to the Twin Cities than have come at any one time in at least a decade, but the payoff will be debated long after they go.

Business and civic leaders in Minneapolis have spent three years prepping for an event that will showcase the region in a way that is seldom possible. Under the banner of "Bold North," they want visitors and viewers of the game, the most-watched TV event of the year, to see a region that thrives even in deepest winter — and to think of it as a place to do business or visit.

"Our city is so primed for opening a lot of people's eyes," says Trace Jacques, a design principal at ESG Architects in Minneapolis. "People are going to come here and say, 'Wow, we've overlooked this place a little too long.' "

Of course, the immediate economic impact of the game is large. About 125,000 people are expected to come to the Twin Cities this week, more than the 2014 All-Star Game in Minneapolis and perhaps more than the 2008 Republican National Convention in St. Paul. Last year's biggest event, a volleyball tournament, brought 48,000 visitors to Minneapolis.

Estimates of the economic impact — money that is added to the region that wouldn't be here otherwise — range from $220 million to around $340 million. Those estimates don't include what fans spend on the game itself, revenue that flows to the National Football League. As big as those numbers are, even the highest estimates represent a mere thousandth of Minnesota's $300 billion economy.

Beyond their large number, the Super Bowl visitors are coming at a time when business is slower, and they will spend more money than most visitors do at any time of the year.

Meet Minneapolis, which promotes the city for conventions and events, is bringing prospective clients into town this week to see the region's major venues and tourism apparatus running at full tilt. "We want them to see the convention center in action," spokeswoman Kristen Montag said. For the region's hotels, she added, "This is usually the time of year when we are least busy."

But there were also big costs to get the game, led by the $1 billion to build U.S. Bank Stadium from 2014 to 2016, half of which came from taxpayers.

"We created U.S. Bank Stadium for other reasons, for the Vikings, maybe they would leave without it, and in the interest of regional economic development of the Twin Cities. Then, the NFL responds with the Super Bowl," said Paul Vaaler, a law and business professor at the University of Minnesota. "The question we ought to be asking is whether the investment is worth it."

Public spending on sports venues is hotly debated in every city and roars around Super Bowls because the NFL is seen as rewarding cities that build stadiums by placing the game in them. The foundation of U.S. Bank Stadium was just being laid when the NFL announced in May 2014 that it would get the 2018 game. Frequently, the debate zeros in on estimates of the economic impact of the game and the 10 or so days of events before it.

"It becomes a focus by both the people who are happy to have it come, including bearing some of the inconveniences, and the naysayers who think the NFL is taking advantage of the host cities," says Kenneth McGill, an economist with Rockport Analytics, a Philadelphia-area firm that routinely studies the economics of the Super Bowl and other large events.

Rockport forecast the $340 million economic impact figure for Super Bowl LII and says Minnesota will see around the same gain that Houston and San Francisco experienced the last two Super Bowls but less than the gains of the hosts before them — Phoenix, New York and New Orleans — where visitors spent more days before the game.

Visitors should account for about 70 percent of Super Bowl-related spending in Minnesota, Rockport forecasts, with the rest coming from event operations, media and sponsor activities. About half the visitors will spend four nights in the Twin Cities and spend $620 a day, the firm forecasts.

Later this week, Rockport will have 30 people working at various Super Bowl events to question visitors about their spending. It will combine that information with data being collected by local and state authorities and produce a final report later this year.

In Houston, Rockport found that visitors didn't spend as much on hotels as it had forecast. McGill said Houston's huge supply of rooms, more than 80,000, meant that prices didn't rise as much as expected. But the opposite may be happening in the Twin Cities. With only 42,000 rooms, rates at Twin Cities hotels appear to be higher than Rockport estimated, but McGill said it's too soon to tell what the effect might be. Fans might adjust by staying a shorter time or veering into options such as Airbnb rentals.

Rockport does not estimate the extra spending that people who live in the Twin Cities might do because of the Super Bowl. And in reaching the $340 million figure, it has subtracted about $70 million of spending that the region is losing from the normal flow of visitors. They have been displaced by football fans, sponsors and media taking up flights and rooms.

The company last year provided an estimate for Bloomington's unsuccessful bid to host a World's Fair-like expo and found that it would take weeks for the event to match the impact of the Super Bowl. "We saw the expo would produce slow and steady increases in visitations," McGill said. "The Super Bowl brings it fast and furiously."

Minneapolis last hosted the Super Bowl in 1992, when it was in the Metrodome and there was less buildup and fewer activities before the game. The area around the stadium has since redeveloped in conjunction with the tearing down of the Metrodome and replacement with U.S. Bank Stadium.

Since 2014, nearly every developer pondering a project in downtown Minneapolis factored in the Super Bowl. Early 2018 became a target date, or turning point, that influenced schedules and costs.

Hotels emerged as the priority, with a dozen or so built in Minneapolis, St. Paul and the suburbs, several near the stadium. The J.W. Marriott at the Mall of America will host one of the teams. Some hotels didn't get done in time, including one at the airport and a couple near the stadium.

But even without the Super Bowl, Minneapolis has booked events at the stadium, convention center and other sites that will draw more visitors than the city saw in 2017. The X Games will return to the stadium for a second time this summer, drawing about 37,000 people. Next year, the NCAA Final Four is likely to draw more than 50,000.

"Even though a couple of projects didn't get open in time for the Super Bowl, they're looking forward to the follow-on effect of a successful Super Bowl," Jacques said.