Some allies grumbled that such framing was an effective way to win over only postdoctoral students, not a broad-based political coalition.

Most of the contrast that Ms. Warren drew early on with her rivals was more high-minded and process-oriented than visceral. It wasn’t until Michael R. Bloomberg, the former New York mayor, entered the race that her attacks turned more personal.

One of the first times she called out Mr. Buttigieg by name was to demand that he reveal his McKinsey consulting clients and open his fund-raisers to the press (there was also, along with Mr. Sanders, the “wine cave” fund-raising attack). There was the ambassadorships ad saying she was the only Democrat pledging not to appoint big donors.

And in Denver a week ago, she pegged the “big diff” between her and Mr. Sanders to be on the filibuster, talking through the arcana of how Senate parliamentary procedure is used to enact an agenda of “big, structural change.”

“‘I have a plan’ — it’s an intellectual argument,” Mr. Trippi, the Dean campaign manager, said. “Ten-point plans just don’t have as much emotional appeal.”

Mr. Begala, the former Clinton adviser who called Ms. Warren’s biography “as compelling a story as anybody in the race,” pointed to her campaign’s decision not to rely on a polling firm as a challenge that most likely made it harder to determine how the candidate best connected with voters. In 1992, he said, the Clinton campaign did not realize the power of his biography almost until deep into the race.

“You know what? I certainly hope when she goes to a doctor, she lets them use a thermometer. I’m sorry I have contempt for that view. To professionally measure and strategize is not to be inauthentic,” Mr. Begala said. “She doesn’t go with her gut on health care or Wall Street regulations. She talks to experts — and she is one herself.”