Many Warren advisers and allies think the Sanders camp has long tolerated public attacks on her from his surrogates, and believe he is not reining in divisive and in some cases sexist attacks against her among Sanders supporters on Twitter.

And the Sanders camp is even more frustrated over what they see as an orchestrated, dayslong campaign by Ms. Warren to revive her bid by suggesting Mr. Sanders is a misogynist.

Sanders advisers believe Ms. Warren has hurt herself with the accusations but also put them in a no-win situation, in which they are unable to fully strike back for fear of appearing insensitive but risk incurring damage of their own without rebutting her claims.

Ms. Warren’s decisions at Tuesday’s debate to openly challenge Mr. Sanders’s denial of that remark, and then to confront him after the debate and refuse to shake his hand before the cameras, have also led Sanders supporters to believe that she is acting underhandedly.