COUNCIL BLUFFS, Ia. — Elizabeth Warren's microphone cut out about 10 minutes into her first speech in Iowa Friday night, but the Massachusetts senator, unfazed, yelled across the crowded room anyway as her staff worked to restore the sound.

When the audio returned, Warren said she was glad, "because this part I want you all to hear, for sure."

"I’m in this fight because I am grateful," she said. "My daddy ended up as a janitor, and I had a chance to become a public-school teacher, a college professor and a United States senator. I am grateful to America down to my toes. I am grateful. But I’m also determined. I’m determined that we build an America where not just the children of rich people get the chance to build something, but where all our children get a chance to build a real future."

That progressive populism defines Warren's politics, and Friday was the first time she pitched it directly to Iowans who will help decide her fate in the state's first-in-the-nation caucuses.

Warren's trip — her first to Iowa since 2014 — caps a week in which she took significant steps to formalize her 2020 efforts by launching a presidential exploratory committee and hiring a team of veteran Iowa staffers. Her route across the state includes stops in deep blue Polk County, as well as events in western and rural Iowa where Republicans substantially outnumber Democrats.

Marilynn Leggio, a 71-year-old Council Bluffs resident, said she was impressed with Warren's style after listening to her speak Friday night.

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"There’s a lot of them to listen to, but I really think she connected with people," she said. "There’s just something about her."

Leggio said she caucused for Vermont Sen. Bernie Sanders in 2016, but said she would not be supporting the independent senator who came within a half a percentage point of toppling frontrunner Hillary Clinton in the 2016 Iowa caucuses.

"I think we need to leave that behind and go in a new direction," she said.

More than anything, Leggio said she wants a candidate who can defeat President Donald Trump in a general election.

While the weekend trip was Warren's first for years, Iikely Democratic caucusgoers already like what they know of her. She came in fourth in a December Des Moines Register/CNN/Mediacom poll and 70 percent said they had a favorable opinion of her.

'This is how it starts'

The event space next to a Council Bluffs bowling alley almost immediately filled to its 300-person capacity when the doors opened at 5 p.m. Friday night. Staffers opened up a garage-style door and set up speakers so another 200 could listen from outside.

Warren greeted the crowd outside as she made her way into the building.

"This is terrific," she said. "This is how it starts: person to person, town to town across Iowa and then across America. We’re going to build a grassroots movement."

Warren spoke inside for about 20 minutes, highlighting her story of growing up in Oklahoma, especially after her father suffered a heart attack and was out of work.

"(My mother) walked to the Sears and she got a minimum wage job," Warren said. "And that minimum wage job saved our home and it saved our family. And if you want to know who I am, that story is etched on my heart and always will be."

She said, over and over, that systems are tilted in favor of big companies, corporations and lobbyists and not the American middle class.

"Why is the path so rocky for so many people and so much rockier for people of color?" she asked.

"It is an America right now that works for the rich and the powerful, and we need to call that out for what it is: corruption, pure and simple."

Then she opened the event up to questions from the audience for another 20 minutes. She addressed issues related to health care, national security and immigration, all the while weaving in biographical details and hammering on the theme that the government is no longer serving the people.

Warren's first Iowa trip takes her through red counties

Warren kicked off the tour in Council Bluffs Friday night. On Saturday, she traveled to Sioux City in Woodbury County, which voted firmly in favor of Donald Trump in 2016 but supported Democratic Congressional candidate J.D. Scholten in the 2018 midterms.

"I think visiting a place like Sioux City is going to teach you a lot about other communities in Iowa as well as throughout the Midwest and the Rust Belt where manufacturing jobs and other economic opportunities may have changed in recent years," said state Rep. Chris Hall, D-Sioux City.

In Sioux City, Warren was asked about the October DNA test she released that showed she had some Native American heritage.

“Why did you undergo the DNA testing and give Donald Trump more fodder to be a bully?" a women asked her.

Warren said she was glad to be asked about it.

"My decision was we’re just going to put it all out there. It took a while, but just put it all out there," she said. "I can’t stop Donald Trump from what he’s going to do....But what I can do is, I can be in this fight for all of our families."

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On Saturday, Warren also headed to rural Storm Lake in deep red Buena Vista County where registered Republicans outnumber registered Democrats 36 percent to 26 percent, and about 48 percent are independents.

Art Cullen, Pulitzer Prize winning editor of the Storm Lake Times and a voice for rural Democrats, said it's notable that Warren chose to stop in his often overlooked town on her first visit to Iowa.

"My advice to Democrats in rural Iowa is to show up. And she’s showing up," he said. "Tom Harkin showed up there. Berkley Bedell showed up there. J.D. Scholten showed up there and damn near beat Steve King. The independents are still a huge number of voters in the 4th District, and they aren’t necessarily racist. It's just that nobody’s talking to them."

Warren ended the day Saturday in Des Moines, where a capacity crowd of 750 people showed up to hear the senator sounding every bit a presidential candidate. Another 300 people showed up but there was no space for them inside so Warren visited them in an outside overflow space.

Sunday she's scheduled to host a conversation with female leaders in Ankeny, a Des Moines suburb where Democrats are gaining power.