Downtown Dallas Inc. is going after Amazon HQ2 with one goal in mind. The nonprofit advocate organization for the city's urban core isn't pitching one specific site. Instead, it wants Amazon to select any location from the center of the city to inside the 2.5 mile radius around downtown.

That includes separate proposals from developers disclosed this week in the broader downtown region, such as: The Exposition Park offer to build between Deep Ellum and Fair Park led by Madison Partners, Trinity Groves owner's bid in West Dallas with developer KDC and architecture firm Gensler and Victory Park's bid led by Hillwood Urban and Hunt Realty Investments.

"Downtown has a great competitive advantage because of Amazon's predisposition to cities," said Kourtny Garrett, chief executive officer of Downtown Dallas Inc. Amazon's specs issued on Sept. 7 with its surprise announcement that it wants a second headquarters was urban vs. suburban agnostic, Garrett said. And urban areas have popped up throughout the D-FW region, but downtown Dallas is at a point in its evolution that it's not the place that shuts down at 5 p.m. that Boeing looked at 15 years ago, Garrett said.

"We can build a Seattle-type environment which Amazon is very proud that it had a role in building in downtown Seattle," she said. Amazon included in its specs that other companies have made $38 billion in direct investments in the Seattle economy since Amazon moved downtown in 2010.

The technology and e-commerce giant is looking for a place to build a second location to complement its Seattle headquarters starting in 2019. Amazon's $5 billion investment includes an estimate of as many as 50,000 employees

That would be a huge prize for Dallas' urban core, which has momentum and made progress in the last 10 to 15 years with its Arts District, Main Street development, 50,000 residents and 93 miles of DART rail lines that all meet downtown and connect far flung neighborhoods to D-FW Airport. There are plans to expand mass transit here, linking more of the region and filling in downtown.

The downtown group is working with Dallas Mayor Mike Rawlings' office, the city's economic development staff and the Dallas Regional Chamber "because Amazon made it clear that it wants a single response from the MSAs," Garrett said in an interview. "That allows for infrastructure and incentives to be layered in the response with the best sites that meet or exceed our needs."

Downtown has several options for Amazon's initial need of 500,000 square feet of office space in 2019. The central business district has 4 million to 6 million square feet of existing available space and an additional 29 million square feet of sites to build-to-suit, Garrett said.

The sites have all been mapped and are near downtown locations for a proposed high-speed rail between Dallas and Houston, near the Design District or on the east side where there are vacant parking lots or south of City Hall into the Cedars area. Another area that is on a new light rail plan around N. Field St. and Ross Ave. has several parking lots and potentially could partner with the West End area, she said.

"It's a large geography and with the revitalization over the last 20 years, there's a lot of opportunity to come into this market," Garrett said.

Downtown Dallas came up with its "360 Plan" in 2011, and it's being updated and shows how important it is for the city to create a complete and connected center, she said. Sites offered to Amazon in the 2.5 mile-radius, would benefit all of downtown, she said.

Light rail and street car additions in the next five years will connect the core of downtown, she said. There's also 50 more miles of bike lanes coming, which would be important to Amazon. Its Seattle workforce uses bikes enough that it built bike cages that are not only rooms to store bikes during the workday, but also have showers.

AT&T's reasoning in staying in downtown Dallas highlight advances there, Garrett said.

"AT&T is a global corporation that wouldn't make a decision to stay in downtown Dallas if it wasn't a smart move for them," she said. "They see downtown as having access to young, talented workforce and an environment that will attract more talent."

AT&T has 5,800 employees in five downtown buildings and is redeveloping the buildings with street level retail that will integrate its offices more into the downtown neighborhood. AT&T has said it's hiring another 500 to 1,000 people to work downtown. Other major downtown employers include Neiman Marcus, Bank of America, Chase, Wells Fargo, Goldman Sachs, Jacobs Engineering, major architect firms, HKS, CallisonRTKL as well as several professional service offices including major law firms and accounting firms.

The 2.5 mile radius now has 50,000 residents, and 20,000 more are projected to move in based on residential projects planned and under construction over the next two years, Garrett said.

Downtown Dallas is also working with the Dallas Independent School District to start meeting the needs of young families that would like to stay downtown but need an elementary school.

"That's how far downtown already is in its evolution," Garrett said.

Twitter: @MariaHalkias

An earlier version of this story misspelled the name of architect firm CallisonRTKL.