"What she did today was remarkable," Wasserman Schultz said. "You could hear the emotion and the power behind the statement she was making because she feels so strongly about this."
After the hearing, Giffords and Kelly met privately with President Barack Obama at the White House.
Giffords has made only a few public appearances and interviews since the January 2011 shooting, including reciting the Pledge of Allegiance at the Democratic National Convention and casting a single vote in August 2011 on legislation to raise the federal debt limit.
She resigned her seat in Congress a year ago to focus on her recovery. Giffords and Kelly, both gun owners, have formed a political action group called Americans for Responsible Solutions that is promoting universal background checks for gun purchasers and limiting the size of ammunition magazines.
Gun control is an issue that really hasn't been debated in Congress for more than 10 years. It rarely gets an airing and engenders strong emotions.
And so it was that both sides did their all to ensure maximum impact from Wednesday's hearing.
Giffords was clearly happy to do her part.
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AP Writer Kevin Freking contributed to this report.