New York Times File Photo / The Democrats keep trying on former Vice President Joe Biden for size, but he doesn't quite fit right yet.

A year before the 2016 presidential election, candidate Donald Trump had a double-digit lead over the 16 other major contenders in the race for the Republican nomination.

A year before the 2020 presidential election, with nearly two dozen major contenders seeking the nomination, Democrats are only united in not knowing what they want.

That fact was evident in the party's debate in Atlanta on Wednesday night where the current front-runners took little fire and the rhetoric fluctuated between the candidates who want to remake the country into a socialist-style democracy and those who would prefer the Franklin Roosevelt federal government-knows-best philosophy with a little 21st-century tinkering around the edges.

Just over two months before Iowa becomes the first state to caucus, three different Democratic candidates lead the first three states to record votes, according to the Real Clear Politics poll averages. South Bend, Indiana, Mayor Pete Buttigieg tops the field in Iowa, U.S. Sen. Elizabeth Warren of Massachusetts leads in New Hampshire and former Vice President Joe Biden has a polling advantage in Nevada.

Biden, according to the Real Clear Politics poll averages, is still clearly the national leader with more than a 12-point lead over Warren.

But almost nobody believes the former Delaware senator is a lock for the nomination, least of all those on the stage at Wednesday's debate. If they did, he would have been the subject of withering attacks and viewers wouldn't be talking instead about exchanges among candidates who have the support of 4.3% (U.S. Sen. Kamala Harris of California), 2% (U.S. Rep. Tulsi Gabbard of Hawaii) and 1.7% (U.S. Sen. Amy Klobuchar of Minnesota) of the electorate.

Biden was content to say as little as he had to, and even then he sometimes struggled to find the right words. At one point, he even said he was supported by the only African-American woman elected to the U.S. Senate. He didn't recall the name of Sen. Carol Moseley Braun of Illinois, a forgettable, one-term officeholder who was elected in 1992. But neither did he remember Harris, who was standing feet away from him.

On the other hand, the other candidates may not have wanted to embarrass the former vice president, who was celebrating his 77th birthday but may not have been celebrating the revelation earlier in the day of DNA results that showed his son Hunter is the father of a 1-year-old, out-of-wedlock child by an Arkansas woman. This is the same son who during the Obama administration was given a plum paid job on the board of a Ukrainian energy firm, the investigation of which is at the center of the Trump impeachment inquiry.

Biden and his fellow candidates — as well as the left-leaning media moderators — may have felt the less said about all that the better, knowing that if impeachment reaches the Senate the Bidens' Ukrainian involvement will get more scrutiny than it's getting in the House discussion.

The candidates also needed to stay in their lane because they can't afford to offend any of the coalition of voters they will need to win the presidency. U.S. Sens. Bernie Sanders, I-Vermont, and Warren can't tack to the center to attract moderate Democrats or Republicans because their far-left wing base won't have it. And pseudo-moderate Democrats Biden, Klobuchar or Buttigieg can't move much farther left without losing the independents or disaffected Republicans who might consider supporting them.

Meanwhile, both Harris and Sen. Cory Booker of New Jersey implied without saying it that a black candidate might be the party's only hope to beat Trump. Both said only a candidate who could cobble together former President Barack Obama's coalition would have the best chance of unseating the president.

Unfortunately for the Democrats, all that speaks to Trump's dogged popularity, despite everything they've thrown at him and every mess in which he gets himself. If he were the pariah among they electorate they paint him to be, they wouldn't have to tiptoe.

Given that, our best guess is they're stuck in neutral until the Iowa caucuses or unless something major happens to change the picture. We've said we believe the House will be unable to keep itself from impeaching Trump, but that's not a game-changer since all the candidates publicly support it (though Biden is likely to worry).

To be sure, several candidates — most likely those not on the Atlanta stage — will drop out for lack of support. Booker, though, begged for enough support to hit the threshold for the December debate on Wednesday and got it.

But it all largely supports the premise: Democrats have fewer than 365 shopping days until Election Day, but they can't decide on a size or a color or a model.