(Bloomberg Opinion) -- If nominations are about defining the party to itself, the Democrats on Night One of the first round of debates made it pretty clear who they are. Demographically diverse. Pragmatic. Liberal. Programmatic. Group-oriented. Competent.Yes, Elizabeth Warren has a plan for that, but so do Julian Castro, Amy Klobuchar and Cory Booker. Some of the others, too, but those are the four who stood out to me. Yes, Klobuchar is relatively moderate, and Warren is relatively more progressive, and the other eight can probably be arrayed on an ideological spectrum based on their answers; still, however, they were very much of the same approach to politics. Take policy seriously. Show solidarity with various party-aligned organized groups and demographic groups: Mothers Demand, unions, climate activists, women and more – and demonstrate it with concrete, specific policy solutions.What Democrats are really like was, I think, best demonstrated by the candidate who in my view had the worst night, Washington Governor Jay Inslee. Inslee is supposedly running on climate. In his closing statement, he tried to differentiate by arguing that he alone is pledging to make it his number one priority if he is elected. And yet Inslee utterly failed to do what a candidate with that kind of plan is supposed to do: Connect every question back to “his” issue to demonstrate that in fact he really would govern that way. Instead, he wound up talking about unions when he got an economy question, and immigrant communities when he got an immigration question – and then, most embarrassingly, he was not among the four candidates who volunteered climate as the nation’s biggest geopolitical threat. Inslee said “Trump,” which is a perfectly good Democratic answer. All his answers were perfectly fine Democratic answers. They just weren’t about climate, and so instead of standing out he faded in with the rest of the candidates who may not qualify for the September debates.In other words, Democrats aren’t really very good at running single-issue campaigns because they are trained, as Democratic politicians, to take policy seriously in all the areas in which Democratic groups want something.Whether this is good or bad, I suppose, depends on one’s sense of what politics is supposed to be about and what one wants from a president. I tend to think it’s very healthy for a party, and a very nice contrast to the bluster and ideological preening that tends to dominate Republican debates even when Donald Trump isn’t one of the candidates.But whether that’s correct or not, what was on display tonight is what the Democrats are.I counted six very plausible nominees going into the evening – Warren, Castro, Klobuchar, Booker, Inslee and Beto O’Rourke. Of those, I suspect that fans of all except Inslee and perhaps O’Rourke will believe their candidate did very well. None of the other four did anything to make me think that they are anything other than distant longshots. But that’s mostly guesswork. As several pre-debate pieces have emphasized, it’s what happens next that determines the winners – what the pundits say, which clips get used on TV news, and which clips go viral on social media. That may take a few days to sort out, especially with a second debate coming Thursday night.Hey, for all I know, the contentious argument between Tulsi Gabbard and Tim Ryan over war in Afghanistan could wind up getting plenty of attention and help one of them (or both) to move up in the polls a little. It was, for whatever it’s worth, one of only two real active arguments, along with Castro and O’Rourke debating immigration policy. It’s not always predictable what the media will do or which clips people will find appealing. What I would say is that neither Gabbard nor Ryan appears to have the support from party actors to take advantage of any surge. Castro and O’Rourke, and Klobuchar, Booker and Warren, are in much better position to leverage a small uptick into something more substantial.Other than that, I’ll stick by my initial sense that this Wednesday group is in fact at least as strong as the Thursday group, even though their polling numbers are far weaker at this point. As a group, they were reasonably impressive despite the difficult logistics of a 10-candidate debate, in which all of them have to fight for time and candidates tend to go missing for half an hour here or fifteen minutes there.And with that, on to the second night.(Corrects spelling of Senator Booker’s name in second paragraph.)To contact the author of this story: Jonathan Bernstein at jbernstein62@bloomberg.netTo contact the editor responsible for this story: Philip Gray at philipgray@bloomberg.netThis column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.Jonathan Bernstein is a Bloomberg Opinion columnist covering politics and policy. He taught political science at the University of Texas at San Antonio and DePauw University and wrote A Plain Blog About Politics.For more articles like this, please visit us at bloomberg.com/opinion©2019 Bloomberg L.P.