They could blow this in the same way they blew 2016: by picking a candidate based on intersectional concerns rather than capacity to unify Americans, and by slandering half the country.

President Trump is not a particularly popular president.

His job approval rating has not crossed 50 percent for a single day of his presidency. He's currently riding as high as he ever has in the RealClearPolitics poll average -- and that's 41 percent. Statistics guru Nate Silver estimates that "the approval rating at which an incumbent candidate goes from being an underdog to a favorite for re-election is somewhere in the high 40s."

Furthermore, Democrats are favored to retake the House of Representatives in 2018 -- they've been dramatically outperforming their poll numbers in special elections. And there's always the possibility that the economy will tank: America has experienced an economic downturn at least once per decade for the past several decades, and our last serious downturn was in 2009.

With all of that said, Democrats can still find a way to blow this.

They could blow this in the same way they blew 2016: by picking a candidate based on intersectional concerns rather than capacity to unify Americans, and by slandering half the country.

Hillary Clinton wasn't the best candidate for president on the Democratic side of the aisle. Then-Vice President Joe Biden polled better. So, in fact, did loony Vermont Sen. Bernie Sanders. Clinton's poll numbers rarely cracked 50 percent and often veered toward 40 percent. And, of course, she was egregiously brittle, supremely inauthentic and tremendously off-putting. Yet the Democratic establishment had determined that it was, in fact, her time -- with the emphasis on her. Clinton was a woman; her rivals weren't. We'd just elected the first black president. It was time for Clinton to break the glass ceiling. And so, the Democrats picked one of the most polarizing figures in American history to carry forward President Barack Obama's legacy.

That was Bad Decision No. 1.

Then there was Clinton's campaign. Clinton spent most of the campaign absolutely bewildered by the fact that a boorish, ignorant reality television star was running neck and neck with her. She could have taken that as a referendum on her own shortcomings. Instead, she took it as a referendum on America's shortcomings. America, she believed, is filled with racist, sexist, bigoted homophobes. America is a basket of deplorables. If it weren't, wouldn't she have been up 50 points?

Of course, Clinton lost.

And all indicators suggest that Democrats intend to copy her playbook.

The single most dangerous candidate to Trump's re-election is, again, Biden. Despite the fact that Biden is a pathological liar with a history of gaffes challenging Trump's own, Biden is a popular figure; he's got blue-collar appeal. But Biden is also an old white man, and the Democratic Party believes that President Obama's coalition can only be replicated by a member of an intersectional minority. Democrats also think that Clinton was too moderate for her own good -- and so, now they're attempting to oust Sen. Dianne Feinstein, D-Calif., in favor of someone more radical. Thus Sens. Elizabeth Warren, Kamala Harris and Cory Booker.

Good luck, guys.

But Democrats have an even worse problem: their obvious disdain for Americans who didn't vote for them. Nowhere has that disdain been more evident than in their treatment of gun owners after the Parkland massacre. Democrats have cheered gun control advocates who question the decency of Second Amendment supporters. They have slandered legal gun owners as uncaring nasties more concerned with preserving pieces of metal than children's lives. They might as well call gun owners deplorables.

Good luck with that one, too.

The dirty little secret of 2016 is that President Trump didn't win the election -- Clinton lost it. Democrats could easily do the same thing in 2020 if they insist that Americans must be taught a lesson for their 2016 heresy.