Presumptive presidential candidate Elizabeth Warren started her trip to Iowa on a high note Friday, impressing a crowd of about 300 people packed into a Council Bluffs bar as some 200 more, who were unable to gain admission inside, watched intently from behind an open window at the back of the room.

Beginning her first visit to Iowa since 2014 in Council Bluffs, a stone’s throw from the Nebraska border, was something of a risky move for Warren. This part of the state tends to lean conservative, though Democrats showed increased strength here in the 2018 elections.

But based on the enthusiasm of Warren’s audience — a mix of die-hard Warren supporters, Democrats just beginning to scrutinize their party’s prospective candidates, and the occasional independent — it was a risk that paid off.

“I’m dead serious when I say this is the fight of our lives,” Warren said. “This is the fight of our lives —and we have been told over and over and over and over, ‘It’s too hard. You can’t do this.’”

After then recounting various times she’s proved naysayers wrong — from toilet-training her child before the age of two to creating the Consumer Financial Protection Bureau — Warren likened her nascent presidential campaign to landmark struggles in America’s past.

“The abolitionists, the suffragettes, the labor movement, the foot soldiers in the civil rights movement [were] told over and over what wasn’t possible," she said. “They got organized. They persisted. And they made change. That’s what we’re going to do.”

Before “they persisted” — a reference to Senate Majority Leader Mitch McConnell’s infamous characterization of Warren as he silenced her criticism of Senator Jeff Sessions, then President Trump’s nominee for attorney general — Warren paused for effect. Afterward, the crowd cheered loudly, the applause growing louder still as Warren brought her speech to its conclusion.

A transcript of Warren’s remarks in Council Bluffs would show that she focused on familiar themes, from the precarious financial state of her own family during her childhood to her current conviction that American society is structured in a way that benefits the rich and powerful few at the expense of everybody else. But on this particular evening, Warren and the crowd seemed to feed off each other in a way that gave her message extra potency.

“I was kind of blown away,” said Scott Punteney, a labor organizer and chair of the Pottowattamie County Democrats. “Pretty impressive. I loved what she had to say. Great crowd, a lot of enthusiasm — it was exciting.”

Punteney, who backed Bernie Sanders in 2016, still hasn’t decided who he’ll support in 2020, in large part because the field is still taking shape. But Warren’s performance in Council Bluffs gave him political déjà vu.

“I’d compare it to Bernie crowds a couple years ago,” he said.

Also giving Warren high marks was Roger Utman of Papillion, Nebraska, a former Republican who’s dismayed by the GOP’s transformation under President Trump and is now an independent.

“I’ve heard Sen. Warren talk a lot of different times on television, but I was really impressed with her tonight,” he said. “We really need to get back and think about the middle class again, because it is disappearing. We have nieces and nephews, and grandnieces and nephews, who, unless something happens, they’re going to have a hard time making it.”

“She’s very personable,” he added. “And instead of talking over you or talking around the question, she addresses the issue."

“Her sense of humor came out tonight,” added his wife, Nancy Utman. “That was really nice. Not only was she relaxed and comfortable ... I think she’s an intense person, and sometimes I think the intensity that she comes across with doesn’t show the warmth that I saw in person.”

While many in the political media questioned Warren’s viability immediately after she formed a presidential exploratory committee, none of the several audience members who spoke with WGBH News raised similar concerns. And none mentioned Warren’s controversial handling of a DNA test which she said confirmed her claims of Native American ancestry, and drew criticism from both the right and the left.

Prior to Warren’s speech, Punteney said that some Iowa Democrats he knows hadn’t been impressed by Warren’s handling of the DNA matter. But afterward, he downplayed those concerns.

“Everybody here, obviously, that’s a non-issue,” Punteney said. “And I don’t know how many people were here, but that place was absolutely packed.”