Less than an hour before the latest Iowa Poll on Democratic presidential contenders was to come out, I was sitting for an interview with Elizabeth Warren in the downtown Des Moines Hilton lobby, getting a sense of what it might show. We could barely get through a question without being interrupted by enthusiastic fans wanting to connect with her. Earlier, at the Polk County Steak Fry, the applause for Warren had been louder and more sustained than for any other candidate. People had waited two hours in line to get selfies with her. And the kernels of corn stacking up in jars with her name on them went higher than other candidates'.

Warren was on, ebullient, engaged. Asked where she got the energy after a grueling day, she said, “I feel so optimistic because nobody’s on the sidelines anymore. People are in this fight." That infectious optimism may be the single most effective factor in vaulting her into Democratic frontrunner status in Iowa. She said “hope” is the word she hears most from people after her stump speech – and "I don't do a very flowery stump speech."

Like Sen. Bernie Sanders, whom she still calls a friend though they are competing now, Warren passionately articulates what’s not working for America and why. She offers progressive solutions, such as Medicare for all and a wealth tax on the top one-tenth of 1 percent of income-earners.

But unlike Sanders, who excited a progressive base in 2016, or former Vice President Joe Biden, whose familiar name had him leading all the polls early on, Warren tells stories of perseverance and triumph. She recalls an America in which hard-working people who fell sick or suffered a job loss had a safety net. She tells her own story of growing up in Oklahoma City, the daughter of a janitor and a homemaker, and ending up in the U.S. Senate “because I was in an America that was building a future for all its children."

It's the seamlessness of the narrative, the weaving in of history and economics, the connecting of dots between workers' struggles, the rise of the labor movement and the passage of worker-protection laws that make her vision plausible. And it's the bottom-up nature of her campaign.

"When I made the decision to run for president, I knew what I'd be fighting for," Warren said. "But it was also important to me how I would be fighting. I wanted to build a grassroots movement ... I decided not to spend time behind closed doors with millionaires. The political establishment said I couldn’t possibly make that work."

She was also criticized for funneling all her small-donor donations into hiring field organizers, she said. But the "person by person, community by community" approach that so-called experts dismissed seems to be paying off. She engages with people as if each is equally important, whether it's the woman who stops by the table to tell Warren her most effective attribute is her raised eyebrow, or the man Warren said had put his dog up in her face and it chewed on Warren's ear.

I wondered if harking back to a better America of the past didn't echo Donald Trump’s 2016 campaign call to “make America great again." As candidate Kamala Harris quipped in her speech Saturday, some of those "great" times were before women and minorities had rights. Better “exactly for whom?” the California senator asked.

Trump gave people reasons to show up, though some of those reasons “were really ugly,” Warren said. She thinks of 2020 "as a chance to build the America of our best values. There was a time we invested heavily in public colleges but denied admission to students of color. We must invest in education but this time, let’s make it work for everyone.”

She recapped at length a speech she gave last Monday in New York’s Washington Square Park about Frances Perkins, the secretary of labor and first female Cabinet secretary under President Franklin Delano Roosevelt. Perkins had been executive secretary of the New York City Consumers League in 1911 when the Triangle Shirtwaist Factory fire claimed 143 workers' lives because exit doors were locked from the outside. Half a million people later showed at a union march, Warren said, “And Frances goes to Albany, gets a committee appointed to look into the fire at a time when women can’t vote. And the committee persuades state legislators to hold safety drills in factories." FDR took Perkins along when he advanced from New York's governor to U.S. president.

“It’s amazing what one woman leading from the inside can get done," Warren said. "I see this as structural. It’s not just a one-off about wages and contract negotiations. It’s about power.”

But union membership and clout have declined precipitously. In 2018, just 10.5% of American workers were union members, compared to the 1940s and '50s when it was closer to a third. And only 6.4% of private sector workers are unionized. About half the states, including Iowa, have right-to-work laws. Warren speaks often about the legalized corruption that allows corporations to pour money into candidates' campaigns to get laws favorable to them passed. She proposed and set up the federal financial watchdog agency, the Consumer Financial Protection Bureau. But what could she do to boost labor rights? As president, she replied, she would appoint a pro-labor labor secretary and a pro-union majority at the National Labor Relations Board.

I also wondered what Warren has to say about the Democratic voters I regularly hear from who fear America isn't ready for a woman president. They're so nervous about Trump winning re-election that they're reluctant to vote for a woman.

“They don’t say it to me,” she replied.

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