<a href="https://www.nytimes.com/2019/07/18/us/politics/2020-candidates-election-2016.html" target="_blank" rel="noopener noreferrer">These Are the Mistakes Democrats Don’t Want to Repeat in 2020</a>  <font color="#6f6f6f">The New York Times</font><p>WASHINGTON — Democrats still don't agree on why they lost the White House in 2016. But they have absolutely no intention of repeating their mistakes.</p>


Senator Elizabeth Warren in Detroit in June. Democrats are focusing their efforts on Michigan, Pennsylvania and Wisconsin, states Hillary Clinton narrowly lost in 2016 after polling ahead for months.CreditCreditBrittany Greeson for The New York Times

WASHINGTON — Democrats still don’t agree on why they lost the White House in 2016. But they have absolutely no intention of repeating their mistakes.

Whatever they were, exactly.

Was it the loss of working-class white voters or urban black voters? Too much talk of Donald J. Trump or not enough? And what about those Russians?

If Hillary Clinton’s decision to skip campaigning in Wisconsin was a problem, the party has that one covered. Democrats selected Milwaukee as the site of their national convention a year from now.

In Michigan and Pennsylvania, states where Hillary Clinton lost after polling ahead for months, Democratic candidates pop up at coffee shops and farmers’ markets, field questions from audiences in packed high school auditoriums and clog up cellphone voice mail boxes.

“You’re making me confess to a secret,” said Representative Mark Pocan of Wisconsin, a liberal who represents the area around Madison. He explained that his voice mail was full and no one could leave new messages. It’s been that way since the beginning of the year, and he said has no plans to clear it out. “That way I don’t have to deal with the candidates,” he said. “We have a few calling, obviously.”

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From former Vice President Joseph R. Biden Jr., who kicked off his 2020 campaign in a Pittsburgh union hall, to Senator Kirsten Gillibrand’s effort to energize her campaign with a Rust Belt bus tour last week, the presidential candidates are eager to show Democratic voters, officials and activists that they’re fighting the next war — by way of the last one.

Wisconsin, Michigan and Pennsylvania have become an electoral Bermuda triangle for Democrats, with a pull so strong that they’re frequently mentioned at campaign events in Iowa and New Hampshire, where voters will set the course for the 2020 primary race.

“We’ve got to put someone at the top of the ticket who can win in places like Iowa and Wisconsin and Michigan and Pennsylvania, right? We all know that,” Senator Amy Klobuchar told voters during a Saturday campaign stop in Waterloo, Iowa.

The Fiserv Forum in Milwaukee, where the 2020 Democratic National Convention will be held.CreditLauren Justice for The New York Times

Two days later Mr. Biden said his candidacy relies on winning the same set of states.

“I’m accustomed to winning places like Pennsylvania and Ohio, Michigan and Wisconsin,” he told 200 people gathered on the driveway at the home of former Gov. Tom Vilsack of Iowa. “There’s no way a Democrat can get elected president without winning Pennsylvania, you just can’t do it.”

The Rust Belt bus tours and campaign cattle calls are far more about lingering post-traumatic stress from the Democrats’ 2016 loss than any current electoral strategy. While the traditionally blue states are likely to be crucial to Democrats in a general election, none of the three are scheduled to hold their primary vote before Super Tuesday, the dozen-state primary that’s widely expected to winnow the field in early March.

Of course, the 2020 race bears little resemblance to the last race — or any other primary in modern electoral history. The crowded Democratic field is four times as big as it was at its largest point in 2016, historically diverse and features the widest age gap ever seen in a primary contest. Democrats may have new opportunities in states where demographics are shifting like Georgia, Arizona and Texas. And the nominee will face a sitting president, who has shown some eagerness to intervene in the opposing party primary contest.

[President Trump’s re-election strategy involves stoking cultural and racial resentments, just as he did in 2016.]

The field of 2020 candidates is eager to reassure voters that if they win, they won’t take anything for granted, even as they handle the previous Democratic nominee with extreme care. Earlier this year, Ms. Klobuchar quickly called Mrs. Clinton to apologize, after she launched her bid with promises to win in Wisconsin that were seen as a jab at the former Secretary of State.

Still, the implicit critique rings clear to Democratic voters and donors.

“I was one of Hillary Clinton’s finance chairs and unfortunately she didn’t come into Michigan enough. They’re not ignoring us now,” said Barry Goodman, a Democratic donor in the Detroit suburbs who is raising money for Mr. Biden.

In town hall meetings and diner meet-and-greets, Democrats frequently bring up the 2016 defeat, often as an origin story for how they became more engaged in national politics.

“People continue to come up to me to tell me the story of where they were on the evening of Nov. 8, 2016, how it impacted them, how they’ve since become engaged,” said Representative Chrissy Houlahan, a freshman from the Philadelphia suburbs who’s being wooed by multiple presidential candidates for an endorsement. “It’s seared in the collective memory.”

Former vice president Joseph R. Biden Jr. kicked off his 2020 campaign in a Pittsburgh union hall in April.CreditMaddie McGarvey for The New York Times

For others, the shock of that loss transformed them into cable news pundits, eager to project what white Rust Belt voters may — or may not — want in a candidate over what they personally might prefer.

“We have created an electorate full of pundits and strategists, and the result is that we’re puzzling through not who we like but who we imagine someone else will like,” said Senator Brian Schatz, Democrat of Hawaii. “It’s a fool’s errand to imagine who will be appealing to someone else.”

The armchair punditry is only exacerbated by a steady drumbeat of polling on the race. After a period of soul searching, pollsters are once again up and running.

A 2017 report by the American Association for Public Opinion Research, an industry group, recommended some changes to polling, notably improving accounting for voters’ education levels, surveying people closer to Election Day and pressing those who say they are undecided on which way they might be leaning. But mostly, the report blamed the “large, problematic errors” in state polls on a single culprit: Money.

“It is a persistent frustration within polling and the larger survey research community that the profession is judged based on how these often under-budgeted state polls perform relative to the election outcome,” the report noted.

But Charles Franklin, the director of the Marquette Law School poll in Milwaukee, who helped craft the report, says while it identified some problems and suggested solutions, none were a “magic bullet.” He’s back in business for the 2020 election, with some tweaks to how he surveys voters who say they’re undecided.

“At least, we have to be self-aware of what we are doing,” he said. “You look at all your data and everything you do and you make some adjustments, but in the end you have to trust your data, recognizing that the data can be wrong.”

That’s certainly a lesson President Trump remembers. His campaign is trying to recapture the magic by running on the same message of cracking down on immigration, race-baiting and skepticism toward conventional political wisdom — starting with ignoring what he calls “phony polling.”

Senator Cory Booker campaigned in Milwaukee.CreditTannen Maury/EPA, via Shutterstock

“I’m going to do it the same way I did it the first time,” he said in an interview with ABC News last month.

Democrats remain far more divided over what lessons their party should draw from the last race.

“There’s something fundamental about the fact that Trump presented himself as a noxious human and still won that is disconcerting and unsettling about America,” said Adam Jentleson, a Democratic strategist working for a group focused on suing Mr. Trump. “But the why, we don’t know. It depends who you talk to.”

Senator Elizabeth Warren rarely mentions Mr. Trump in her stump speech, focusing instead on her plans for transforming the country’s economy. Mr. Biden takes nearly the exact opposite tack, weaving his opposition to the current president into nearly all parts of his argument. His supporters argue that the race will be won by convincing moderates that the Democratic nominee is a safer choice than Mr. Trump.

“We’ve got to get moderate working-class Democrats back,” said former Gov. Ed Rendell of Pennsylvania, who’s backing Mr. Biden. “We’ve got to get candidates that they can relate to.”

Senator Kamala Harris, meanwhile, argues that the path to victory for Democrats runs through energizing the women, people of color, and younger voters that make up the backbone of the party.

Her campaign, along with others in the party, believes that mobilizing these voters in cities like Detroit, Milwaukee and Philadelphia could make the difference in the three states in question.

“There are things we all understand about what happened in 2016 aside from Russian interference,” said Adrianne Shropshire, who runs BlackPAC, an African-American political organizing group. “What is clear is that there were key segments of the Democratic base that stayed home.”

Others think that Democrats should spend less time and money in traditional swing states like Ohio and Iowa and instead focus on shifting their map into the rapidly changing Sun Belt, where they found success during the 2018 midterms.

All the uncertainty has left some Democrats urging voters to take a truly radical stance: Just vote for who you believe in.

“Put your money on someone who energizes and excites you,” said Mr. Jentleson, “rather than someone who appeals to a voter in a diner in rural Michigan who you invited in your head.”

Lisa Lerer reported from Washington and Reid J. Epstein reported from Waterloo, Iowa.