In 12 ½ years in Congress, he sponsored and wrote only one bill that he steered to enactment: a measure pushed by a family friend who gave his campaigns tens of thousands of dollars in donations. …

Yet the more lasting impression left by Mr. Weiner, according to more than three dozen people interviewed, was of a go-it-alone politician whose legislative record was thin and whose restlessness could spill into recklessness. He smartly selected issues on which to weigh in but left the difficult legislating to others, they said.

“It was like he had a megaphone surgically attached to his mouth,” said former Representative Zachary T. Space, Democrat of Ohio. “His unwillingness to be a team player did compromise his ability to be an effective congressman. I don’t care if you’re a congressman, or president, or mayor or a city councilman — you can’t do it yourself.”