Mrs. Clinton showed a tendency toward an insular management style, relying on a coterie of aides who have worked for her for years, her aides and associates said. Her choice of lieutenants, and her insistence on staying with them even when friends urged her to shake things up, was blamed by some associates for the campaign’s woes. Again and again, the senator was portrayed as a manager who valued loyalty and familiarity over experience and expertise.

Mrs. Clinton stood by Mr. Penn and Patti Solis Doyle, who was until last month her campaign manager, even as her campaign was at risk of letting Mr. Obama sew up the nomination. When some of her closest supporters pressed her to replace them, arguing that the two were clearly struggling with their jobs and had become divisive figures in the campaign, she responded by saying she would “think about it.”

When Mrs. Clinton finally pushed out Ms. Solis Doyle, she chose Ms. Williams, like Ms. Solis Doyle, an old friend who had never before managed a presidential campaign.

Mrs. Clinton’s ability to manage the one person with whom she spoke most often, former President Bill Clinton, was also questioned by some of her advisers and supporters. Mr. Clinton moved in his own orbit  he heatedly argued with his wife’s advisers who wanted to write off South Carolina, defying them to campaign there  and took no direction from the campaign about what to say or where to go, some of them said. (Mr. Obama defeated Mrs. Clinton in the South Carolina Democratic primary by nearly 29 percentage points.)

Several aides, donors and supporters, who requested anonymity to recount private conversations with the candidate, said they had warned Mrs. Clinton that her husband’s attacks on Mr. Obama were demeaning to her and hurting her campaign. Mrs. Clinton replied that her husband became “carried away” at times but that she did not see any real harm from his approach, they said.

Mrs. Clinton’s top advisers said that while her management style might be untidy, it showed her to be comfortable with conflicting ideas among her aides. They said she had pronounced herself “ready to learn” from her mistakes and was resistant to placing too much power in the hands of a single political adviser in the mold of Karl Rove in President Bush’s two campaigns for the White House.

“She thinks the way to manage effectively is to get a lot of smart people around who don’t agree and let them work out their differences creatively,” said Howard Wolfson, her communications director. “Let them hash through things, and as a result, you come up with the best process.”