(CNN) Sen. Elizabeth Warren arrived in Iowa on Friday evening and, through four events over a little more than 24 hours, quickly made clear that even as her presidential campaign evolves, she is poised to rise or fall with the same brand of wonky populism that took her from the classroom to Capitol Hill.

In speeches to packed rooms from the state's western border with Nebraska to its capital in Des Moines, Warren spent the weekend demanding "structural change" in Washington, where the partial government shutdown is entering its third week. She wants "to strengthen our unions, our workers and our consumers" while breaking the hold of an "army of lobbyists" occupying the capital, as she describes it, under the banners of "big corporations."

Even during her occasional strolls in the policy weeds, Warren, who has set the tone for her remarks so far by opening them with the story of her mother's struggle to find a minimum wage job to help save their house after Warren's father suffered a debilitating heart attack, keeps up a low fury. When her microphone cut out at the opening event in Council Bluffs, Warren didn't yell because, even in a room of 300 (with 200 more outside) she didn't have to.

"There are too many people who get their power from turning working people against working people," the Massachusetts Democrat said a day later in Storm Lake during a riff on long-stalled talks over comprehensive immigration revisions. A few hours earlier, in Sioux City, she declared, "Washington keeps working great for those with money, but not for anyone else. We need to call this out for what it is: It is corruption, pure and simple."

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