Joe Biden’s recent jump to clear front-runner in the 2020 Democratic nomination contest is being credited to the concept of “electability” – the belief that Biden, of all Democrats seeking the nomination, would represent the most formidable nominee against President Trump.

And with Democrats’ anger at the incumbent at a boiling point, and continued disappointment at the 2016 outcome, there is supposedly a willingness by many Democrats to compromise their real attitudes and just ensure that Trump leaves the White House.

Not so fast, some people reply, pointing out the list of times when major parties chose to nominate the “Most Likely to Win” candidate – only to wind up losing in November, while at other times parties went with their base love and wound up moving into the White House.

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Both lists are fairly long: “Most Likely to Win” candidates include Republican Mitt Romney in 2012 and Democrat John Kerry in 2004 – both of whom lost to incumbents that the opposition considered vulnerable.

“Base Love but November Poison” candidates arguably include Ronald Reagan in 1980, Barack Obama in 2008, and, of course, Donald Trump in 2016. They defied predictions.

Biden’s Democratic rivals suggest that they, too, have very solid chances of beating Trump in November 2020, pointing to polls that have almost all of them ahead of Trump in head-to-head matchups.

For most folks, the word electability suggests the candidate who appears best positioned to attract moderate voters – the people most likely to be choosing between the two major parties.

Historically, electability has not been a major factor in primaries. Primary voters tend to be more reflective of the base of their parties. Democratic primary voters tend to be more liberal, while Republican primary voters tend to be more conservative than general election voters.

The primary voters typically find candidates that fit their personal party visions to be more attractive than compromising their positions to nominate someone closer to the middle.

I call it “Mishkin’s First Rule of Primaries: He who runs in a primary claiming to be stronger in the general loses the primary.” (Note to those who think this is sexist: “She” has historically not been a candidate who claimed electability.)

In the two most recent cases where parties sought a nominee against an incumbent president, electability turned out to be decisive. This happened in 2004 when the Dems picked Kerry to run against President George W. Bush and in 2012 when the Republicans picked Romney to run against Obama.

In each case, the Fox News exit polls in primaries showed a small minority of voters saying they made their decision based on electability, but members of that smaller group invariable were going for Kerry and Romney – and their votes tended to make the difference in enabling those candidates to win primaries.

Of course, in November each of those supposedly electable candidates lost.

What does that mean for 2020? Are Democrats smart to focus on electability?

Recent history suggests the Dem focus on electability is not wise, but there may be some peculiar reasons why it might make sense this year.

In fact, the concept of electability flies in the face of the way politics, particularly presidential elections, have been waged in recent years. Rather than fighting to convince folks in the middle to choose one candidate over the other, the general election is about ensuring that as many of one’s base supporters get to the polls as possible.

Forgive the nerdy inside-baseball nature of this discussion, but it goes to the heart of how American politics is now waged. For years, political professionals would argue about what is more important. Was it “persuasion” – convincing people that your candidate was superior to the opponent? Or was it “motivation” – ensuring that your supporters get to the polls?

Most people in politics will say you need to do both. While they’re correct on one level, the emphasis of most political campaigns has moved from persuasion to motivation in recent years.

Part of this is a simple result of technology.

The first big shift in political campaigns started in the 1960s through the 80s with the growth of television. The shrewdest campaigns would divert almost all of their budgets to television advertising – which (by the nature of television) reached a wide audience and so had to focus on issues of interest to a wide variety of voters, meaning it had to concentrate on persuasion.

But in recent years, with the growth of segmented television programming -- together with more targeted direct mail, and most recently, individually targeted social media advertising -- campaigns have been able to focus more and more both on identifying their core supporters as well as working to ensure that these supporters vote.

The high-water mark for this may have been George W. Bush’s 2004 re-election effort. Chief campaign strategist Karl Rove realized that there were few, if any, truly undecided voters, and decided to focus the campaign primarily against ensuring high turnout of core supporters.

Several statewide referenda against gay marriage in Ohio and elsewhere helped to fuel turnout of evangelical voters and enabled Bush to eke out a re-election win.

But it was, as well, a key component of Obama’s wins in 2008 and 2012. Obama’s stratospheric appeal in 2008, combined with voter reaction to the fall 2008 financial crisis, made his victory almost a foregone conclusion. But those factors should not obscure the enormous success the Democrats had that year in driving turnout of base Democratic voters, particularly African-Americans.

According to the 2008 Fox News exit poll, over 20 percent of African- American voters said it was the first time they had voted. By contrast, only 6 percent of whites said it was their first vote. That turnout was responsible for Obama victories in hard-to-win Electoral College-rich states, including Florida and North Carolina.

In 2012, Obama -- with a slow economic recovery, and the divisiveness of the Affordable Care Act -- did not do as well with the middle as in 2008, becoming the first president re-elected while reducing his popular vote margin. But he continued to command high support – and high turnout – from base Democratic voters.

By contrast, his opponent Mitt Romney (who’d won the nomination in part due to his perceived electability) failed to galvanize the Republican base. The best evidence for that is the actual vote in Ohio, where Obama won even though he had fewer votes than McCain four years earlier. Romney’s base just didn’t show up.

In 2016, Republican candidate Trump clearly had a very energized base, which carried him to the nomination despite claims that he’d be a sure loser in November. He wasn’t, obviously, in large part because while the Trump base turned out, the Democratic base seems to have stayed home, particularly in Michigan, Pennsylvania and Wisconsin.

The lessons of the past four elections – 2004 through 2016 – suggest that the foundation of electability resides not in the ability to persuade the moderate, independent, voter, but in the ability to motivate the core supporters of a party.

So when candidates such as Sen. Kamala Harris, D-Calif., argue they would be more electable than Biden, they make an important point: The word electability may be code for “appeal to the middle” – but the concept of electability is often more dependent on the ability of candidates to appeal to, and motivate, their respective bases.

That said, three other things may be at work, that all relate to Biden’s electability. They help explain why polls suggest that Democrats are flocking to Biden following his announcement, as the candidate who “will beat Trump.” Arguably they may be more important than a nerdy, inside-baseball look at electability.

First is a belief that the biggest motivator for the Democratic base in 2020 will not be the individual they nominate, but the incumbent president. The huge turnout in 2018 was arguably less related to the quality of their candidates than to Democratic opposition to Trump.

Democrats believe that their base is highly engaged and likely to turn out, regardless of the identity of their eventual nominee. In that environment, it’s less important to have a candidate who can galvanize the base, and more important to identify a person who would appeal to the middle and to disaffected Republicans. Biden clearly appears to fill that bill.

Second, in an atmosphere of Democratic hostility to Trump, there is a clear desire on the part of Democrats to identify an individual to “take him on.” Get the nomination contest over with, and find the candidate who can tweet back and seek the level of attention that Trump is able to command.

As one politically astute, Trump-hating observer said to me: “We’re in a national emergency, we don’t have time for silly Democratic backbiting, they should close down the campaign, and identify the torch-bearer.”

Finally, there is the question of impact on the non-presidential races, which is obviously important to party leaders. For all Obama’s success in two successive presidential elections, his era also saw the loss of 12 seats in the Senate, 63 in the House, and control of over 14 state Legislatures.

While the Dems regained significant strength in 2018 in Congress and the states, they still have enormous ground to make up. Considerable evidence exists that when a party is led by a candidate who appears to be “a risk,” significant numbers of voters choose to vote for the other party down ballot.

In fact, that’s precisely what happened in 2016, when voters were wary of Hillary Clinton -- the candidate the media assured them would win. Instead, they chose to vote for many Republicans in races appearing lower on the ballot.

Unlike others, Biden carries the aura that voters will be comfortable with him.

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So if you use electability the way it’s historically applied, you’d say that Biden may not be the ideal candidate to enthuse the Democratic base. But if you consider electability to be a way of uniting the party quickly around a candidate who can go head-to-head against Trump – and ensure comfort with a Democratic win -- then he just might fit the bill.

Is Biden the only one? No. Does he still have vulnerabilities? Yes. But it explains why he’s doing so well in the run-up to the start of caucus and primary voting in February.