President Barack Obama delivers his State of the Union speech before members of Congress in the House chamber of the U.S. Capitol Jan. 20, 2015 in Washington, DC. Getty

As the final year of President Barack Obama’s presidency begins, a promise he made long ago is once again in the administration’s crosshairs. The president — just shy of seven years since he signed an executive order demanding that the still-open Guantanamo Bay detention facility be closed within his first year in office — has been transferring prisoners at an accelerated clip in an attempt to push Congress to act.

In the days before the president’s final State of the Union Address Tuesday, where he will outline his plans, administration officials began reiterating promises that the facility is coming to the end of its twilight years. Even though the president has tried to frame the place as an expensive terrorist recruiting tool, Republicans have already shown it’s unlikely they’ll work with Obama. Aside from being a difficult task, closing the prison could also be politically dangerous for the 2016 elections if national security remains a major voter concern for one simple reason: Public approval for closing the prison is low.

“He feels an obligation to his successor to close that, and that’s why we’re going to do it,” Denis McDonough, White House chief of staff, told Fox News Sunday.

Protesters in orange jumpsuits, including one in plastic shackles, from organizations including Amnesty International USA rally outside the White House to demand the closure of the U.S. prison at Guantanamo Bay, in Washington, D.C., Jan.11, 2016. Reuters

So, How's He Going To Do It?

Obama hopes to push Congress into action by lowering the population of Guantanamo through repatriation of prisoners deemed to be less of a threat. They have already released four individuals this year. That brings the total down to as little as 103 still in the prison of the 780 who have been locked up there. The fewer inmates in Guantanamo, the higher the cost of the facility — which was $397 million in 2014 — per inmate will become. Obama hopes that will convince fiscally conservative Republicans in Congress to shut off the lights there.

“My expectation is by early next year, we should have reduced that population below 100. And we will continue to steadily chip away at the numbers in Guantanamo,” Obama said during his end of the year press conference for 2015 last month. “There’s going to come to a point where we have an irreducible population — people who pose a significant threat, but for various reasons, it’s difficult for us to try them in [court]. Now, at that stage, I’m presenting a plan to Congress about how we can close Guantanamo.”

President Barack Obama speaks during his end of the year news conference at the White House in Washington, D.C., Dec. 18, 2015 Reuters

What Does This Mean For 2016?

Since Obama’s inaugural month in office in January 2009, support for closing the prison has dropped quite a bit, according to the public opinion polls conducted by Rasmussen Reports through the years. The last poll conducted one year ago shows support for closure was just 29 percent of likely U.S. voters compared to a high of 44 percent in 2009. But, there’s more reason to expect increased heightened opposition to closing the terrorist prison. Voters, concerned about recent terrorist attacks in Paris and San Bernardino, California, are more likely than before to say that national security is a top concern for 2016. That includes 40 percent who think terrorism should be the government’s top priority and 60 percent who put it in the top two, according to a December Wall Street Journal/NBC News poll.

That said, national security experts have warned that the facility has been used as a terrorist propaganda tool for recruitment purposes. That opinion is one that former President George W. Bush, who oversaw the opening of the prison, has shared alongside Obama. The facility is generally used as a symbolic measure to paint the U.S. as a hypocritical and amoral.

Whatever Americans think about Guantanamo in general, at least one of Obama’s potential Democratic successors, former Secretary of State Hillary Clinton, has pushed for the facility’s closure in the past. When leaving the president’s State Department, she wrote a memo urging him to get rid of the prison.

And now there’s one year left for him to heed her request.