AS a key pollster for Senator Barack Obama’s presidential campaign, Joel Benenson has a job that would typically make him one of the most sought-after voices in the candidate’s inner circle. But that status depends on who the candidate is.

“I’ve worked for Barack for 12 months, and in 12 months, he’s asked me twice about poll numbers,” said Mr. Benenson, who has worked over the years for many politicians in the metropolitan region, including former Gov. Mario M. Cuomo of New York and Senator Robert Menendez of New Jersey. “I’ve never worked for a candidate who asked less about polls.”

It is not that his candidate is not interested in how he is perceived by the public, Mr. Benenson is quick to point out, but rather that Senator Obama is so confident about his message  that he offers a real change  that he doesn’t use poll results to dictate his latest platform, as Mr. Benenson implied some other candidates do.

Still, Mr. Benenson and his polling data have played a critical role in helping crystallize the messages not only of Senator Obama, but of several other candidates that he or his company, Benenson Strategy Group, has handled over the years, including a New York City mayoral candidate, Representative Anthony D. Weiner of Queens; former Gov. James E. McGreevey of New Jersey; and the Clinton-Gore team in 1996.