An official from Toronto has called Amazon's search for the second headquarters "the Olympics of the corporate world."It's a unique situation of its kind and scale. Typically, cities and states vie for factories or offices behind the scenes. This time, Amazon's public solicitation of bids from essentially all major metropolitan areas in North America has prompted reporters and analysts across the continent to run their own odds on potential winners.What's at stake?The top-line pitch is Amazon's promise to invest $5 billion in whatever community it picks to be the home of its second headquarters. And the company says it would bring up to 50,000 new jobs, with an average salary of more than $100,000.In Seattle, Amazon's towering 8.1 million-square-foot downtown campus employs tens of thousands of employees and has served as a testing ground for new retail ideas, like a store without checkout registers. Amazon says HQ2 would be a "full equal."What is Amazon looking for?The company's call for applications is extremely detailed. It should be a metro area with more than 1 million people, a business-friendly tax structure, close to an international airport and near major highways, a place with mass transit, good Internet and "excellent" higher education. The company is also not shy about saying it wants an attractive offer of a financial incentive — a move that has become customary for corporate expansions, which often involve tax cuts, relocation grants or fee reductions. "The initial cost and ongoing cost of doing business are critical decision drivers," Amazon says in the request for proposal.Whicht communities are vying for the HQ2?With almost four weeks until the deadline, the list of potential contenders is expansive: Austin, Texas; New York, Boston, Chicago, Washington/Baltimore, Atlanta, Denver, Ottawa and Toronto — cities up and down and across the continent, tallied to number more than 100 by the Chicago Tribune.And the communities aren't shy about their public pitches."We have sites that are ready, that are transit-oriented," says Scott Levitan, head of the Research Triangle Foundation in North Carolina. "We have tremendous fiber backbone at our site and we have a region that is absolutely focused on being the best possible location for HQ2," he says, adding that the Raleigh-Durham-Chapel Hill metro area sits equally between the ocean and the mountains."Colorado is perfectly aligned with the company's culture of collaboration and innovation and focusing on its customers," says Yuriy Gorlov, vice president of the Aurora Economic Development Council, also highlighting the Denver area's access to fiber, power, transit and a nationally recognized hiking trail system."We feel like we have a lot to offer, in terms of our talent base, our logistics, our business-friendly climate," says A.J. Robinson, president of Central Atlanta Progress. "And most of all, people love to live and work here."(Note: Amazon is one of NPR's financial supporters.)What are the cities' biggest considerations or potential concerns?Though Amazon likes to tout the billions of dollars it says it has injected into Seattle's economy, the city has been tested by the massive corporate presence. Over the years, frustrations aired by residents of Seattle (headquarters there employs 40,000 employees) have included rapidly rising housing costs, traffic congestion, gentrification and pressure on local businesses. As The New York Times reported recently: