A revealing new book from one of media's longest-serving White House correspondents reports that President Obama surrounds himself only with "idolizers," and top aides make sure that those whose views might "shake him up too much" are shoved aside.

In " Prisoners of the White House, the Isolation of America's Presidents and the Crisis of Leadership," U.S. News correspondent Kenneth T. Walsh also discloses the extent to which Obama relies on polling for his political decisions, including a never-before revealed re-election project to investigate the thoughts and feelings of "up for grabs" voters and another dedicated to helping him build a lasting legacy.

Walsh, who has covered the White House for 25 years and written several books on the presidency, credits Obama for trying to get out of the so-called "bubble," but found that instead the president often relies on a tiny cadre of Chicago aides, thus living in "a bubble within the bubble."

He called top Chicago aide Valerie Jarrett "one of the leading idolizers" who blocks the access of critics to her boss. "Jarrett has gone too far in limiting others' access to the president, according to a number of White House and congressional sources," writes Walsh in the book, due out June 1. "Her goal is to keep Obama in a cocoon of admirers who won't, in her mind, shake him up too much or present views that might be contrary to her understanding of Obama's positions."

Democratic pollster Peter Hart told Walsh that Obama is more a performer than seasoned politician. "He likes performing. He likes crowds," said the pollster. But Hart added that Obama's White House is too distant from those in Congress who can help him. "It's closed. It's insular. It's shut out."

The book from Paradigm Publishers also reports that the president has been meeting with scholars to plot out his legacy. The most recent was a January dinner of salad and pastry-wrapped beef. "Obama discussed history with his guests for two hours. He was particularly interested in their thoughts on how he could ensure a successful second term and what kind of legacy he could create," reports Walsh of Obama's meeting with seven scholars.

Walsh, who writes about presidents going back to Franklin D. Roosevelt in his new book, also tells of an Obama re-election initiative called the "ethnology project" in which his pollster looked at the thinkings and feelings of undecided, or "up for grabs" voters. The findings of hours of interviews and questionnaires on a select group of voters from Ohio, Florida and Colorado helped steer Obama's reelection campaign.

But Walsh gives Obama credit for trying to stay in touch with his middle class roots and normal Americans, noting that the president has kept his Blackberry to email friends despite concerns by the Secret Service, trolls through news sites and reads letters from Americans to his wife at night.