I watched, took notes and decided on who had the best night -- and who had the worst. They're below.

WINNERS

* Pete Buttigieg: The former South Bend, Indiana, mayor proved Tuesday night that he is the best debater in this field. But he also did something more important than that, too: In the first 30 minutes of the debate, Buttigieg showed a competency, steadiness and depth of knowledge coupled with personal experience that should help him pass the commander-in-chief test in the eyes of voters. He spoke forcefully and powerfully about his issues with President Donald Trump's approach to Iran and the need to go back to the drawing board on Congress authorizing the use of military force. It's also worth noting that despite Buttigieg's status as one of the top-tier candidates in the contest, he rarely seems to be on the receiving end of damaging attacks from his opponents.

: The Massachusetts senator delivered the line of the night, noting that the four men on the stage had lost 10 races while the two women on stage -- she and Minnesota Sen. Amy Klobuchar -- had never lost a race. And wasn't just a zinger that will be quickly forgotten, either; it's an effective pushback against the idea that she is too liberal to beat Trump. While Warren seemed somewhat shaky during the foreign policy discussion at the start of the debate, she found her way into things when talking about health care -- demonstrating a commitment to aiming big, a contrast between her approach (on everything) and that of Buttigieg and former Vice President Joe Biden.

* Amy Klobuchar: The Minnesota senator went into the debate with a simple goal: Cast herself as a pragmatic alternative to voters looking for someone other than Biden (or, to a lesser extent, Buttigieg) to vote for. She, generally speaking, accomplished that goal -- although Klobuchar was less of a standout in this debate than in the last one. (Her inability to remember Kansas Gov. Laura Kelly's name was more than a little cringe-worthy.) Would Klobuchar have hoped for a little more of a star turn in this debate? Yes. Will she be broadly happy with her performance? Also, yes.

* Policy: The most common critique of these presidential debates is that the focus is on personalities, not policies. I hope those critics watched Tuesday night's debate. There was lots and lots of policy -- health care, childcare, foreign policy, climate change -- and very few personality-focused questions. If you were a potential voter tuning into this debate to learn about where the top candidates stand on the major issues of the day, you got what you were looking for.

* 1990: The back-and-forth between Warren and Vermont Sen. Bernie Sanders over whether she was the only person on the stage to beat a Republican incumbent over the past 30 years led to a remarkable amount of debate over how long ago, exactly, it was. Also, speaking of 1990, that got me to thinking about 1990 -- when the : The back-and-forth between Warren and Vermont Sen. Bernie Sanders over whether she was the only person on the stage to beat a Republican incumbent over the past 30 years led to a remarkable amount of debate over how long ago, exactly, it was. Also, speaking of 1990, that got me to thinking about 1990 -- when the Milli Vanilli lip-synching scandal broke (look it up, kids!), "Twin Peaks" was on broadcast TV (still can't believe that happened) and the "Teenage Mutant Ninja Turtles" (Damn you, Shredder!) were all the rage. Man, those were the days.

LOSERS

* Joe Biden: If Buttigieg is the best of the debaters among the top six, then the former vice president is the worst. On Tuesday night he consistently seemed to forget or misstate a point, forcing him to go back and restate it to make sure he got it right. It made for a halting performance, in which he came across as less forceful and sure of himself than others on the stage. Biden also spent a lot of time talking about mistakes he had made on past votes -- support for the war in Iraq being the most prominent -- which doesn't strike me as how his campaign wanted him to spend much debate time. With all that said, Biden hasn't been a terribly good debater throughout this process -- and it : If Buttigieg is the best of the debaters among the top six, then the former vice president is the worst. On Tuesday night he consistently seemed to forget or misstate a point, forcing him to go back and restate it to make sure he got it right. It made for a halting performance, in which he came across as less forceful and sure of himself than others on the stage. Biden also spent a lot of time talking about mistakes he had made on past votes -- support for the war in Iraq being the most prominent -- which doesn't strike me as how his campaign wanted him to spend much debate time. With all that said, Biden hasn't been a terribly good debater throughout this process -- and it hasn't had any major impact on his poll numbers . And Biden didn't make any sort of catastrophic mistake that would disqualify him or badly stunt his current support in the four earliest voting states.

* Bernie Sanders: Sanders' dismissiveness about Warren's statement that he had told her a woman couldn't win the White House in 2020 -- "I didn't say it," he claimed -- bothered me. Sanders tried to portray the issue as immaterial -- hatched by Republicans and the media to distract voters. But it's not. Warren herself said -- on the record! -- that when she told Sanders she thought a woman could win, " : Sanders' dismissiveness about Warren's statement that he had told her a woman couldn't win the White House in 2020 -- "I didn't say it," he claimed -- bothered me. Sanders tried to portray the issue as immaterial -- hatched by Republicans and the media to distract voters. But it's not. Warren herself said -- on the record! -- that when she told Sanders she thought a woman could win, " he disagreed. " (Warren reiterated that stance in the debate.) Sanders did effectively contrast his record on the war in Iraq and on trade with Biden. But he was somehow on the outside looking in when the subject turned to "Medicare for All" -- it was mostly Warren vs. Buttigieg -- and never had any sort of even decent answer to the question of the actual costs of his programs.

* Tom Steyer: Simply put, the billionaire businessman looked badly out of his depth. He struggled badly to make the case that he was better equipped than his rivals to manage the country's foreign policy -- his answer amounted to the fact that he has traveled a lot internationally (and, no, I am not kidding) -- and things didn't get much better for him from there. For most of the debate, it felt like the Top 5 were involved in one conversation and Steyer was just, well, there.