It didn't affect Corker politically. He scored a resounding win last month, cruising to re-election with 65 percent of the vote.

"I can count. I went to public schools in Tennessee and learned that to pass a bill it takes 60 votes and I know we have 45 going into next year," he said in an interview with The Associated Press. "I came up here to solve problems, not to score political points, and yes, it was rewarding that after throwing ourselves into the most controversial issues there were and trying to solve things pragmatically we ended up in the place where we were in this last race.

"I'm more energized than I've ever been," he continued. "The last two years of my first term were like watching paint dry because nothing was occurring and it was fairly discouraging and one has to ask oneself is this worth a grown man's time."

There were some doubts whether Corker, who made a fortune in real estate and had promised to only serve two terms, wanted to come back for more of a Congress riven by dysfunction and partisanship.

"At times I wondered if he would really run again," said Tennessee Gov. Bill Haslam, who has known the senator for decades ever since Haslam's older brother, Jimmy, the new owner of the Cleveland Browns football team, roomed with Corker at the University of Tennessee. "It kind of frustrates him, admirably so, when people aren't focused on problem solving."

Tom Ingram, a political consultant who has worked on Corker's campaigns, said the senator deliberated on whether to run again. "He had to convince himself it was something worth doing before he did it," Ingram said.

So Corker is back, with a black notebook that he grabs every morning to jot down problems and what he'd like to accomplish in a Senate where Democrats have strengthened their majority to 55-45, from 53-47.

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