Are Democrats about to hand the GOP another 1968?

Viewed in the abstract, the year of the anti-Vietnam-War protests, the assassinations of leaders like Dr. Martin Luther King, Jr. and Robert Kennedy, and the "Summer of Love" should have been an electoral layup for the Left. Instead, in the 1968 presidential election Americans handed the White House to one of the Left's most hated enemies, Richard Nixon. Why?

Not because the Vietnam War was popular, or Americans were experiencing a conservative revolution (that wouldn't happen until Reagan in 1980). And it certainly wasn't Nixon's charm and charisma. Liberals, who owned the issues of the day, lost at the ballot box because they pushed too far. To paraphrase Barry Goldwater, extremism in defense of liberalism is no way to win elections.

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Today is not 1968—thankfully. Cities aren't on fire, leaders aren't being assassinated and political violence is largely limited to fiery social-media rhetoric. (Though with some disturbing exceptions). But Democrats are in danger of pushing themselves out of the political mainstream on the eve of a midterm election that, for all sorts of historic reasons, should be an easy win.

In just the past week, Democrats have staked out progressive positions that would have been beyond the political pale just a few months ago. When 28-year-old unknown Alexandria Ocasio-Cortez defeated longtime incumbent Joe Crowley, for example, she loudly embraced the #AbolishICE movement—a political meme sprung from the pages of the far-Left Nation magazine. After Ocasio-Cortez's shocking upset, Nancy Pelosi dismissed the suggestion that her race was a sign of her party's leftward movement.

"Our party is a big tent," Pelosi said. "Our districts are very different one from the other."

But just days later, prominent Democrats like Massachusetts Senator (and potential presidential candidate) Elizabeth Warren, New York Senator Kirsten Gillibrand and New York City Mayor Bill de Blasio had taken up the call—a call for what sounds to most Americans like "open borders" or "no enforcement at all," no matter how much Democrats talk about their plans for a commission to study enforcement issues.

As former Democratic pollster Mark Penn told The Hill, most Americans don't agree. In fact, 84 percent of Americans favor handing undocumented immigrants over to federal agents, he reports.

And a new Harvard/Harris poll also found that 69 percent of Americans—and 59 percent of Democrats—oppose disbanding America's immigration law enforcement agency.

Republicans who shrug off the passionate opposition inspired by the scene of sobbing mothers at the southern border are no doubt making a mistake. President Trump realizes that, which is why he's backed so far away from the policy so quickly.

But Trump, who has displayed an almost visceral understanding of how Middle America feels about issues of the day, also sees the assault on ICE as a self-inflicted wound for Democrats.

"Well I hope they keep thinking about [abolishing ICE]. Because they're going to get beaten so badly," Trump said on Fox News. "I love that issue if they're going to actually do that," he added.

This isn't good news for Democrats in Indiana or Missouri, who'll be forced to explain their party's support for abolishing ICE in a nation where Americans oppose increased legal immigration by a 2-1 margin. Although that percentage has been dropping, for now, the problem red-state senators have is that's exactly what their base wants to hear.

There's something else the base wants to hear: Anger.

On the Supreme Court nomination, liberal activists want a fight to the death. As the New York Times reports, "They want their senators to do nothing less than lie down on the tracks to stop Mr. Trump's nomination."

It's not extremism in policy but extremism in practice. Some liberal academics are urging Democrats to pack the Supreme Court—add seats to give a future Democratic president a majority of total appointments. As Ian Samuel of Harvard Law put it: "Pack the courts as soon as we get the chance. 'Pack the courts' should be a phrase on par with "abolish ICE."

Calls for court-packing are the "nuclear option" on steroids, and no Democrat in Congress has embraced Samuel's call for court-packing yet, but it's not hard to imagine it could be in the Democratic mainstream by the midterms.

And then there's the issue of simple civility. Americans are fundamentally nice. They don't like boorish behavior from their president or their co-workers or anyone else. And they're unlikely to respond well to scenes of liberal activists showing up at the homes of office holders like Ajit Pai of the Federal Communications Commission or White House staffer Stephen Miller. Or, as infamously occurred at the Red Hen restaurant in Virginia, refusing to serve White House press secretary Sarah Sanders based on her politics.

Most Americans don't want politics to protrude so deeply into our personal lives. Unfortunately for Democrats, nearly half of their voters do. A new poll finds that 49 percent of Democrats supported the restaurant owner who refused to serve Sarah Huckabee Sanders. More than 80 percent of Republicans and 53 percent of independents disagreed.

When a sitting members of Congress, Rep. Maxine Waters, D-California, publicly calls for her supporters to "harass" members of the government they see "in a restaurant, in a department store, at a gasoline station," it gets cheers from the hardcore base. But for swing voters, shouting at people just trying to eat dinner or get gas is not the style of politics they support.

In the end, how Democrats campaign may not matter. History is on their side in this midterm election, and if this November turns into a "base vs. base" election with low turnout from swing/moderate voters, having an angry, energized party could be an electoral winner.

However, it is also possible that all the passion and confrontation could scare voters—particularly older voters, who tend to turn out disproportionately for midterm elections—into opposing what they see as a disturbing level of extremism.

If Democrats underperform in November, the culprit could be their over-exuberance today.