Do vice presidential picks matter? Conventional wisdom argues they have limited electoral impact.

But a vice presidential pick does matter in a particular way to elections. It suggests the strategy and tactics a campaign will pursue. The pick might complement the ticket, like Al Gore did for Bill Clinton in 1992, or the pick might balance the ticket, like Mike Pence did for Donald Trump.

So Joe Biden's electoral fate may well hinge on this decision. In our polarized era, where turnout determines election victors and each party's coalition has become more locked in, ticket-balancing picks for vice president can be helpful in mending primary wounds and generating excitement for the coalition in the general election.

That is why Biden should select for his running mate a ticket balancer.

Now, the temptation for Biden to pick a ticket "complementer" will be high. All the conventional wisdom suggests that ticket complementers "do no harm" because they are, essentially, prototypes of the presidential nominee.

By contrast, ticket balancers offer voters something the main nominee lacks and often are meant to motivate a group within the coalition with which the nominee has struggled to gain traction. Balancers are perceived to be riskier, especially since John McCain's selection of Sarah Palin in 2008.

Hillary Clinton is often castigated as running a terrible, horrible, no good, doomed campaign. She actually ran a perfectly fine campaign — but strategically speaking, it was the wrong kind of campaign. It was based on the flawed assumption that a significant portion of American conservatives would not, simply could not, vote for Donald Trump.

But on Election Day, 90% of Republicans voted for him; Clinton also failed to carry independents, despite a campaign structured mostly on winning them over.

Clinton's "do no harm" pick — Sen. Tim Kaine of Virginia — ended up doing her considerable harm. The strategy built around the pick ended up leaving the party's progressive flank vulnerable to, among other things, a sophisticated Russian propaganda and disinformation campaign.

In addition, so-called protest balloting in 2016 was three to five times higher than normal in the swing states. In states like Wisconsin, which was decided by less than a percentage point, nearly 6% of the electorate cast protest ballots. For all the attention placed on white, working-class voters and their continued realignment away from Democrats, protest balloting affected the outcome of every swing state contest and played a pivotal role in Trump's destruction of the Democrat's Midwest "blue wall."

Yet Trump still has a plurality problem, and his campaign manager, Brad Parscale, knows it. Even before the pandemic came along to destroy his best argument for re-election, the economy, Trump was unpopular among independents and has hardly ever (aside from a brief moment early in the coronavirus crisis) hit 50% approval rating nationally and rarely in swing states.

The only way to re-elect a plurality president is to make a plurality vote share sufficient enough to win. And the best way to do that is to replicate Russia's playbook of targeting parts of the Democratic coalition — like progressives and young black voters — to turn them against voting for Biden.

The only person who has as much riding on Biden's decision is Trump. As in 2016, he hopes to pick off or discourage disgruntled progressive voters. Much of Trump's re-election hopes are pinned on Biden making the wrong choice of running mate.

So the Biden team must make a pick that can help Democrats match what promises to be an energized Republican base. The best way to do that is a ticket-balancing candidate like Stacey Abrams or Kamala Harris. They would bring gender and racial diversity to the ticket and, perhaps even more important, ideological diversity.

That might prove to be the single most effective way to head off the Trump campaign's "divide and conquer" plan for progressives in 2020. With 120 million millennials and Generation Z potential voters now powering their coalition, Democrats would be wise to recognize that their electoral fate hinges on getting these voters to the polls. Biden is positioning himself as a bridge to the party's future — and liberals like Harris and Abrams would help pave the way.

Another ticket-balancing approach would be to put a down payment on the Democratic Party's geographic future. This approach would focus resources not as much on the Midwest but on Sun Belt states from California to Georgia through Texas, which could rise as a potential swing state as early as 2024. This would have the Biden team looking at Michelle Lujan Grisham, the Latina governor of New Mexico, or at Sen. Catherine Cortez Masto of Nevada as potential running mates.

Biden's nomination maxes out the ticket's appeal to the center of the electorate. Among independents, the pandemic, economic collapse and Trump's antics already provide Biden a hard edge. A centrist, ticket-complementing pick like Sen. Amy Klobuchar of Minnesota will likely bring diminishing returns in this regard. As a fellow white moderate, Klobuchar is a quintessential ticket complementor — a 2020 version of Kaine.

If Biden is going to ignore the fact that today's Democratic Party represents the most racially diverse coalition in America's history, he should at least look to a ticket balancer like Sen. Elizabeth Warren of Massachusetts, who would bring ideological diversity and guarantee robust turnout and loyal support among progressives, many of whom are independents.

The special election last week in California's 25th District shows Democrats are still vulnerable to low turnout; when their coalition fails to turn out, they lose. It also dispelled a dangerous myth — suburban Republicans are not casting ballots for Democrats. If Democrats want to hold on to or even expand on their House gains from 2018 and potentially take control of the Senate, they need an excited electorate.

Election outcomes in key states like Michigan, Wisconsin, Pennsylvania, North Carolina, Florida and Arizona all come down to the same thing: the percentage of Democrats and left-leaning independents that end up casting ballots compared with the percentage of Republicans and right-leaning independents that do so. Republicans understand this campaign math and learned to solve this equation a long time ago. The only question is, have Democrats finally solved it too?

Rachel Bitecofer (@RachelBitecofer) is an election forecaster and senior fellow at the Niskanen Center. She wrote this article for the New York Times.