Washington — For months, Representative Gabrielle Giffords, who was shot in the head in an assassination attempt last year, signaled that returning to Congress, something she desperately longed to do, was in the realm of the possible.
She listened pensively as her friend, Senator Kirsten Gillibrand of New York, briefed her on the conflict in Libya, and she expressed in clipped phrases her views on the matter. She cast a vote to raise the nation’s debt ceiling. Her Congressional aides continued to churn out news releases outlining her positions and hold community meetings, and she and her husband gave an interview to ABC News in which she demonstrated her improving ability to speak.
But Ms. Giffords, a moderate Democrat from Arizona whose remarkable comeback stirred the nation, decided in recent days that she could not continue her recovery and still serve as a member of Congress. On Sunday, she announced that she would step down.
Ms. Giffords’s decision shook up the race for her seat representing Arizona’s Eighth District. She barely fought off her Republican challenger in 2010 but was expected to be a shoo-in for re-election if she had decided to run this year.
“She could have definitely done it,” Ms. Gillibrand said. “But I think she made a realization, if she really wanted to focus on the recovery, she shouldn’t.”