Story highlights Former Rep. Gabby Giffords and her husband Mark Kelly will endorse Hillary Clinton

The move comes almost exactly five years after Giffords, then an Arizona Democratic congresswoman, was shot in the head

Hooksett, New Hampshire (CNN) Former Rep. Gabby Giffords and her husband Mark Kelly on Sunday endorsed Hillary Clinton, stating that she is the only "candidate for president that has the determination and toughness to stand up to the corporate gun lobby -- and the record to prove it."

The move comes almost exactly five years after Giffords, then an Arizona Democratic congresswoman, was shot in the head ago during an appearance in front of a Tucson supermarket. She barely survived and stepped down from her House seat to recover. She and her husband, a retired astronaut, have become outspoken advocates for tighter gun laws. The couple have founded a political action committee, Americans for Responsible Solutions, to push their new project.

"Time and time again, Hillary has done and said what is right, not what is politically expedient. That's why we are supporting her for President of the United States," the couple said in a statement to CNN.

The couple's endorsement -- which is tied almost exclusively to Clinton's position on gun control -- is a personal decision for the family, and does not mean their PAC, Americans for Responsible Solutions, will back Clinton.

"Most of the people running for president talk a lot about how tough they are. But most of them have shown they aren't tough enough to stand up to the gun lobbyists. Nobody knows better than us that talk is cheap," the couple says in their endorsement of Clinton.

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