How did this happen?

The field of candidates for the Democratic Party's presidential nominee was more diverse than ever before: women, African-Americans, Latinos, young, dynamic, optimistic and yes, gay. There were so many candidates with so many varying political views that they couldn't even all fit on the stage for the first debate and the televised showdown needed to be split over two evenings.

That was in June 2019. But now, more than eight months later, it seems most likely that the nomination has been narrowed down to two choices: One is a 77-year-old former vice president who is as well-known for his verbal gaffes, forgetfulness as for his hugs that lack all sense of boundaries. The other is a 78-year-old senator who suffered a heart attack in October, proudly calls himself a "socialist," hasn't revealed how he will pay for his generous policies and is generally known for his stubbornness.

One of them doesn't have a real plan to speak of, and the other has a plan that doesn't have a chance of winning the support of most Americans.

Majority wants a moderate candidate

Results from Tuesday's primaries show that Democratic voters want unity — and they are ready to vote for the person they think can beat President Donald Trump in November's election. The fundamental political goals are clear: Democrats feel it's the role of government to help the poor and weak, they are in favor of (some form of) universal health insurance and rational gun control laws, and they want to fight climate change and support measured foreign and defense policies.

The majority also wants a moderate candidate and does not support Bernie Sanders' extreme, uncompromising views. That's led Democrats to support Joe Biden after his formidable victory with nearly 50% of the vote in South Carolina, which led other moderate candidates like former mayor Pete Buttigieg and Senator Amy Klobuchar to drop out of the race and endorse Biden. There is strength in shared values, and everyone likes to support a winner.

Let's imagine for a moment what the results might have been if the primary process had been different and the Democratic Party leadership had shown some strength. Or if leaders had decided what political direction the party should take or even had offered voters a choice between the moderate Klobuchar and the progressive Senator Elizabeth Warren. Two smart women who look to the future and have the added advantage of knowing how to form coalitions.

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Imagine if the Democrats showed some spine

A united Democratic machine that enjoys the support of the party's big names, like Joe Biden, whose contributions to the party during his long career are undisputed, and Bernie Sanders, who has shown he can motivate young voters better than anyone, would have helped either Klobuchar or Warren beat the current president.

But the party bigwigs ducked their responsibility and left the decision to voters. And voters were simply overwhelmed. Sanders' organization and his excited, engaged young supporters and Biden's name recognition gave the two old, white men insurmountable advantages. The younger candidates never really had a chance.

And now Biden is experiencing the comeback of his life by winning the primaries in states like Minnesota where he didn't even campaign. Sanders trounced Hillary Clinton there in 2016, but Biden took it in 2020 in part thanks to the support of home-state favorite Klobuchar.

Sanders needs to listen to voters' message

The time has come for the Democrats to close their ranks and remember the real goal: Winning the presidential election against Donald Trump. A fight between Biden and Sanders at the Democratic Convention, which could still happen, would be hugely detrimental to that ultimate goal.

If Sanders really wants to get Trump out of the White House, then he should listen carefully to the message voters are sending him. They do not want a revolution; they want a moderate to take over and Sanders should support that — even if the moderate's name is Joe Biden.

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