The goal for them, of course, is to oust Donald Trump, perhaps even take over both houses of Congress, and begin the process of restoring civility in government. Finding the right standard-bearer will be tricky.

I believe the successful Democrat will fit this profile: female, under age 60, established but virtually baggage-free, and left of center without being too far removed from the mainstream comfort zone. In other words, a female version of Obama in 2008.

Why a woman? It's what the country really wants. Hillary Clinton botched it in 2016 because her overwhelming negatives pushed too many voters away from breaking the "glass ceiling." In 2020, a female challenger will give Democrats the energy that comes with not just undoing Trump, but crossing the sexist divide once and for all.

From a purely strategic perspective: as crude as Trump is likely to be in the 2020 campaign, insults aimed at a female opponent will backfire far more than against a male.

Why under 60? Although we're all grateful to be living longer, age is an issue in politics. Come November 2020, Joe Biden, perhaps the best known and widely admired Democrat, will be 77. Bernie Sanders, who stirred more passion than Clinton, will be 79. Elizabeth Warren, the most recognizable at this stage among female Democrats, will be 71. Trump will be 74.

The nation wants, and frankly deserves, a somewhat younger perspective. Strategically, a candidate significantly younger than Trump will have an advantage.

What about baggage? Every politician has vulnerabilities, especially in the fast and fact-free digital era. But some issues, such as Warren's tangled attempts to clarify her Native American heritage, just get in the way. Hillary Clinton, despite significant achievements in government, had more baggage than any presidential candidate in modern times. The party must be more careful.

How far left? Both political parties drift away from center in the primaries and then try to swing back in the general election. But Sanders and Warren, for whom the term "socialist" is frequently invoked, are probably too committed to progressive positions—usually, to their credit—to be relied upon in 2020, when the bottom line is winning.

As we close the book on the 2018 midterms, two Democrats stand out as compelling candidates for 2020: California Senator Kamala Harris, 54, the former state Attorney General, and Amy Klobuchar, 58, the senior Senator from Minnesota.

Both women have been testing stump speeches in Iowa. Klobuchar, tellingly, has refused to pledge that she would serve out her full senate term.

Right now, voters need a timeout. But for leading Democrats focused on 2020, there's no time to waste.

(c) Peter Funt. Distributed by Cagle syndicate.