“We’re not losing,” she said in an interview after the mattress company tour. Through a tight grin, she dismissed an inquiry — whether she would stay in Congress if Democrats lost — as “so D.C., like an insider thing,” and she accused the news media of predetermining the election results. “They’re saying, ‘This is how we see it, so this is how it will be, so prove to us it isn’t,’ ” she complained.

It is hard to find anyone who claims to have heard Ms. Pelosi entertain doubts about winning. “She believes deep in her soul that the Democrats will keep the majority,” said Larry Horowitz, a friend and adviser.

Whether that is denial, superstition, insight or spin is a subject of some debate.