Presidential candidates raise their hands when asked if they would provide health care for undocumented immigrants during the Democratic primary debate Thursday. (Wilfredo Lee/AP)
Contributing columnist

Well, it’s on. After four hours of debate, 20 candidates and a lot of newsreel, we’re finding the roses in the field of a thousand flowers blooming. More than 15 million viewers tuned in to Night 1 of the Democratic debates Wednesday, followed by a Democratic primary record 18.1 million on Night 2. I tried to keep track of the issues, the differences and the candidates who stood out. The two nights did, indeed, produce winners and losers and a few surprising contrasts. Some candidates simply did not belong on the stage, but voters will figure that out.

Women dominated on both nights. Sen. Elizabeth Warren (Mass.) did not disappoint on Night 1, and Sen. Kamala D. Harris (Calif.) threw down on Night 2. Each woman, in different ways, proved she could go toe-to-toe with President Trump. In case there was any question: They are electable.

Warren has a plan for everything, and she used her time to spell them out. She skillfully explained the problem of concentrated wealth in the hands of a very few who are not paying their fair share. She used storytelling to offer policy solutions for a green economy, universal health care, tech sector antitrust, private prisons and more, calling for “big structural change.” Warren’s closing vision was easily the best of the two nights. There was no doubt she meant it when she said: “I’ll fight for you as hard as I fight for my own family.”

Harris simply killed it on Night 2, first by managing the stage when she scolded the other candidates, reminding them that “America does not want a food fight, they want to know how we’re going to put food on the table.” She was commander in chief: The debate was hers, and she did not stop there. By taking on former vice president Joe Biden for his previous statements on working with segregationists in the Senate and his position on busing in the 1970s, Harris made clear that she’s fighting for the nomination. Up until this point, she had flatlined in most polls; I suspect Night 2 changed that.

Others stepped up, too. Night 1 offered a healthy contrast of the range among Democrats on issues from health care to immigration policy to Iran. Former Housing and Urban Development secretary Julián Castro had been largely overlooked until now, but he proved his mettle by taking on former Texas congressman Beto O’Rourke on immigration policy. If you weren’t aware of Section 1325 of the U.S. Code before, thanks to Castro, you know now that it treats illegal border crossings as a criminal matter. Castro wants it repealed; O’Rourke does not.

Sen. Amy Klobuchar (Minn.) was a surprise for the evening. She reminded us of her nose-to-the-grindstone ability to get things done, even in a partisan Senate. And Sen. Cory Booker (N.J.) showed us why he’s earned a closer look. He spoke with authenticity about gun violence in his neighborhood and the need for common-sense solutions.

Obviously, we will see Biden again in the next round. He needs to make a significant course correction for July 30, and I expect he will. And Sen. Bernie Sanders (I-Vt.) will be there, too — though his bark did not seem to have the same bite as it did in 2016.

Harris had such a commanding effect on Night 2 that it was hard for some candidates to stand out. Sen. Kirsten Gillibrand (N.Y.) fought for her time and used it to carve a niche on her policies to support working families. She was most passionate about the role of money in politics and the way it prevents dealing with some of the nation’s most pressing problems, from guns to prescription drugs. The way that Mayor Pete Buttigieg owned up to what’s happening in his city, South Bend, Ind., after the police shooting of a black man — “It’s a mess and we’re hurting” — just might help his candidacy survive. Sen. Michael F. Bennet (Colo.) did not get much airtime, but he used it to illustrate differences with Biden on fiscal policy. This might be an interesting contrast in a narrower field.

I’m looking forward to the next debate. Here’s hoping that come July 30, a smaller field will give us some of the matchups we most need to see. It’s riveting television. I want more.

Read more:

Erik Wemple: Why not let the Democrats actually debate?

Paul Waldman: The first Democratic debate actually told us a great deal

Donna F. Edwards: Democrats need to repackage the Mueller report for TV

Ed Rogers: Ranking the Democrats’ debate performances

Hugh Hewitt: What an awful debate