Theda Skocpol

Opinion contributor

Generals often fight the last war — and the same applies to political parties that try, however myopically, to learn lessons from the last round. Still, how do we explain why so many Democrats seem hellbent on preparing for 2020 not by building on huge 2018 successes, but by misreading their party’s loss in 2016?

In the last presidential go-round, Democrats lost by a hair in the Electoral College while piling up votes in California and other liberal areas. So why does it make sense to tilt the 2020 agenda toward ultra-liberals?

By contrast, the remarkable “blue wave” of 2018 built because ordinary citizens, led by middle-class women, organized everywhere. Unprecedented numbers ran for city and town offices, state legislatures and Congress, while tens of thousands went door to door to turn out voters for both moderate and progressive Democrats. Even candidates who lost provided choices and a voice in public discussions. Democrats cannot prevail without candidates on the ticket; and as the Doug Jones case in Alabama shows, the choice to run has to be made long before unanticipated events make a seat winnable.

Democrats ignore 2018 lessons

November 2016 finally forced liberal Americans to stop focusing all their hopes on presidential politics and, instead, build from the bottom up in all parts of the country. From the 1980s to the early 2000s, U.S. conservatives figured out that governorships and state legislatures are the key to building power.

As Republicans won such posts, they gained the power to gerrymander congressional districts, ram through unpopular legislation, and set rules that undercut the voting and organizational capacities of their opponents. In turn, conservative majorities in Congress — even just a strong plurality in the U.S. Senate — have allowed Republicans to thwart or eviscerate the achievements of even the most popular Democratic presidents, as they did with many of Barack Obama’s initiatives.

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Now, as 2020 approaches, I worry that Democrats are forgetting the lessons many grasped in 2017 and 2018. The first 2020 primary debates were a case in point. Thrilling as it was to see female contenders do well, the debates were chaotic and dominated by simplistic questions about topics of little concern to most Americans. The ostensible winners embraced ultra-left issue stands — like calls to abolish private insurance and give free health care to migrants — that would sink them in the general election.

Democratic voters who want to win in 2020 need to hope that the debates this week and beyond feature better questions and answers. Meanwhile, as an interested citizen and a political scientist, here are three lessons that everyone should keep in mind.

Politics is a team sport

►U.S. politics is not a national contest. Victories in Congress, state politics and the Electoral College all depend on winning majorities or hefty pluralities in heartland states and areas that are not big cities. Hillary Clinton lost in 2016 mainly because she was whomped in non-urban areas where Obama had lost by far smaller margins. Media commentators and lefty advocates often speak as if the United States is one big national polity, where appeals to one demographic slice or another are decisive. But it just isn't so. Piling up votes on the liberal coasts matters not at all, if party candidates lose in Pennsylvania, Minnesota, Wisconsin and North Carolina.

►State politics and the U.S. Senate matter just as much as the presidency. No matter how many great policy plans a new Democratic president has spelled out in position papers, they will not go anywhere if far-right governors and state legislators can block them — or if the Senate stays in Republican hands. When asked about that problem, progressives promise they will call people to flood the streets. Senate Majority Leader Mitch McConnell is likely just chuckling over his whiskey at that notion.

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►Politics is a team sport. This is the most important lesson — to be kept in mind by citizens who need to keep organizing at the grassroots everywhere, by candidates who need to step up at all levels, and by donors and constituency groups. I’m looking at you, peripheral presidential contenders John Hickenlooper (Colorado) and Steve Bullock (Montana). You should withdraw and run for the Senate. And I am really looking at you, billionaire Tom Steyer. Your riches (if not thrown away on vanity projects) could help congressional and state candidates and get-out-the-vote operations.

Don't revert to liberal myopia

Such foolishness does not happen to the same degree among right-wing U.S. millionaires and billionaires. As my research colleagues and I have shown, far-right plutocrats have banded together — especially through theKoch network — to both boost the GOP and shape its agendas in the states as well as nationally. Their counterparts on the left, meanwhile, scatter their resources on personal pet projects, achieving much less impact overall.

In the 2018 cycle, many liberal myopias started to clear. Ordinary citizens, especially women, got involved in communities and states everywhere and led the way to victories for Democrats of all stripes, including for mainstream liberals who can help build majorities again in 2020. Here’s hoping the lessons of 2018 do not get lost as Democrats, once again, embark on contentious presidential politics.

In the United States, the road to national power does NOT run primarily through California, Massachusetts, or the TV studios of MSNBC in New York City. It runs through middle-American suburbs, cities and rural counties. To win in 2020 and beyond, Democrats have to organize everywhere and project a national message that resonates widely.

Theda Skocpol is the Victor S. Thomas Professor of Government and Sociology at Harvard University. Her recent research has focused on the Tea Party and the Koch network in conservative politics, and on the spread of the anti-Trump grassroots resistance group since November 2016.