TAMPA — When it comes to picking battles, Mayor Bob Buckhorn appears more focused on achieving his goals as mayor than on running for governor in 2018.

As evidence, consider how much time, effort and political capital Buckhorn is spending to help President Barack Obama win congressional approval for the proposed Trans-Pacific Partnership trade deal.

Labor unions hate the agreement, also known as TPP. It's also opposed by many Democrats in Congress, as well as by Hillary Clinton and Bernie Sanders.

And Buckhorn?

"We're all in," he said last week on a White House-arranged conference call with national political and business reporters.

So why do something that could only make it harder for him to win a statewide Democratic primary?

Money, for one reason.

City Hall and the Tampa Housing Authority plan to ask the Obama administration for a Choice Neighborhoods grant of up to $30 million. Could it help to build up political good will ahead of time?

"Absolutely," Buckhorn acknowledges. "Relationships are mutually beneficial."

The grant would boost the "West River" redevelopment being planned for the North Boulevard Homes public housing apartments, which are to be demolished, and the surrounding area on the west bank of the Hillsborough River.

But Buckhorn said that's not the only reason he supports TPP.

"I have always had an interest in trade, have always been a free-trader," said Buckhorn, who last summer also supported the administration on a related fast-track trade proposal known as TPA, for Trade Promotion Authority. And he notes that Tampa has the Florida port nearest the Panama Canal, a port that is spending a lot to prepare for the canal's expansion.

Supporters say the TPP deal, a decade in the making, would lower tariffs on U.S. goods and open markets in 11 Pacific Rim nations that make up 40 percent of the global economy.

But opponents attack TPP as a corporate giveaway. They contend it would make it easier to export manufacturing jobs overseas, undermine human rights in countries with poor records on sweatshop labor, open the door to unsafe food products, increase the cost of imported medicine and make it harder to hold multinational corporations to environmental standards.

While St. Petersburg Mayor Rick Kriseman also has supported TPP as "good policy," Buckhorn has been identified as one in a core group of Democratic mayors, including those from Atlanta; New Orleans; Little Rock, Ark.; and West Sacramento, Calif., who plan to lobby Congress for the deal.

In that role, Buckhorn has:

• Chaired a task force for the U.S. Conference of Mayors that supports the trade agreement.

• Appeared as the sole mayor at the table for a meeting of the White House Export Council on the agreement.

• Flown to Atlanta in October during the final round of negotiations on TPP to appear at news conferences with other mayors supporting it. (He reimbursed the city for the cost of the trip a week later. His Washington meetings on TPP have come during trips he made for the Conference of Mayors and other city business.)

• Talked it up to national political and business reporters in conference calls featuring administration officials and business representatives such as the president of the U.S. Hispanic Chamber of Commerce and the policy chairman of the U.S. Cattlemen's Beef Association.

"It's great having Mayor Buckhorn and his colleagues deeply involved in the process," U.S. Trade Representative Michael Froman said last week. "They are close to the ground. They have a keen sense of what it takes to create good-paying jobs in their community."

But anti-TPP activists say they'll remember where candidates stand.

"A true litmus test," West-Central Florida Federation of Labor executive director Cheryl Schroeder said of when the state AFL-CIO screens candidates for governor.

"It's a horrible thing to have on your resume," said Harriet Heywood, state coordinator of People Demanding Action, a national nonprofit advocacy group. "It's done a lot of damage to Debbie Wasserman Schultz," the South Florida member of Congress who chairs the Democratic National Committee. She drew an anti-TPP primary opponent, Tim Canova, after voting in favor of fast-track trade authority.

TPP is one in a handful of state and national issues that offer a mix of political risks and rewards to Buckhorn and his city.

Over the last three years, he has worked to drive local sign-ups for health insurance under the Affordable Care Act and opened city recreation centers to Obamacare navigators.

And on the state level, Buckhorn has come out in support of Gov. Rick Scott's request to add $250 million next year to the state's corporate recruitment and relocation efforts.

Ask Buckhorn why he has taken on these issues, and he provides Tampa-specific reasons for each: It is good for as many Tampa residents as possible to have health care. Expanding global trade benefits Tampa's port, which is connected directly or indirectly to 80,000 local jobs. And it is good for business to bring in new companies.

Besides, it's not like he embraces all of the GOP agenda in Tallahassee. Last week, he opposed proposed open-carry bills and called for the Legislature to expand Medicaid.

Still, as he noted when he stayed on the sidelines during the governor's race between Scott and former Gov. Charlie Crist, he has to work with Republicans on city projects pending in Tallahassee.

City Hall's top priority during this legislative session is securing a second round of funding for the University of South Florida's downtown medical school building. It's part of a planned $2 billion redevelopment being launched by a partnership between Tampa Bay Lightning owner Jeff Vinik and Microsoft founder Bill Gates' Cascade Investment fund.

The Legislature and Scott approved $17 million for the medical school last year. This year, USF is seeking another $22.5 million.

Buckhorn also is asking the Legislature this year for up to $10 million in Amendment 1 funds for his planned $30 million redevelopment of Julian B. Lane Riverfront Park. (Sierra Club leaders in the Tampa Bay area have said the park, planned to have a boathouse, sports fields, playgrounds and event space, is not the kind of natural habitat Amendment 1 was meant to preserve.)

In each case, he hopes positions that help Tampa turn out to be good politics, too.

"There is risk in any position that you take, particularly ones that are controversial," Buckhorn said. But "if I don't do what's right by my city, I don't have a chance of being elected governor. I think my record will speak for itself."