Last week’s Democratic debates gave Sens. Elizabeth Warren (D-Mass.) and Kamala Harris (D-Calif.) a platform to impress viewers and position themselves as credible opponents against President Donald Trump, according to a set of new HuffPost/YouGov polls.

In surveys taken immediately after the first and second debates in Miami, Warren and Harris were widely seen as outperforming in their respective appearances, eroding former Vice President Joe Biden’s perceived edge as the most electable candidate.

Warren, who dominated the opening moments of the first debate, stood out because she “clearly articulated, explained, and defended her policy positions” wrote one Texas woman included in the poll. “She was focused, thoughtful, authoritative, and convincing. She seems to have improved her live performance skills and appeared unflappable. And very capable.”

During the second debate, Harris sliced through her rivals’ crosstalk and challenged Biden on his history with racial issues, such as busing. She was ”[v]ery direct in her plans and outspoken,” wrote another woman, who was polled shortly after that night. “To beat the aggressive president we have now the candidate will have to be just as aggressive.”

The usual provisos about polling apply here: Because poll numbers naturally fluctuate to some degree, be cautious about overinterpreting any changes of just a few points, especially if they’re not borne out in other surveys in the days to come. And with debate polling in particular, caveats include the fact that voters’ pre-existing opinions of the candidates help shape their reactions; opinions remain fluid; and, of course, impressing voters in a debate doesn’t necessarily translate into gaining even temporary ground in the horse race.

Here’s a look at the survey’s results:

So Who Won The Debate?

Whether or not a debate actually lends itself to a single “winner” is itself debatable ― among other things, it’s unclear whether voters really treat the event as a zero-sum game. But the first two debates each saw a clear standout.In the first survey, 59% of Democratic and Democratic-leaning voters who watched at least clips or highlights of the debate said Warren did the best job, with Castro a distant second at 16%, and the remaining candidates all in the single digits.

The second debate saw a similar divide, with 59% of the Democratic and Democratic-leaning voters who watched at least highlights or clips saying Harris did the best, 16% naming Biden, 11% naming Sen. Bernie Sanders (I-Vt.), and everyone else polling below 10%.

Below, a few voters who picked Warren in the first debate explain why they felt she did the best job, many referencing her composure and command of policy:

“She actually has plans instead of just vague talking points.” ― Utah woman, age 29

“She clearly identifies issues and has policy plans to address them. She’s direct and articulate about the mistakes being made by the current administration. She hasn’t got time for nonsense.” ― Kentucky woman, age 64

“She answered the questions well, she didn’t pivot often and tended to stick to the subject material. She was prepared as always, and didn’t engage in excessive crosstalk or interrupting” ― Oregon man, age 27

“Best at articulating actual policies and plans that I understand and agree with not just a bunch of the usual political double talk.” ― California man, age 57

“She’s brilliant. She’s got a PLAN.” ― Florida woman, age 59

Many voters who thought Harris performed best in the second debate cited her presence and debating ability:

“I think she is a warrior. She impressed me the day she announced. I believe Kamala Harris has what it takes to beat Trump and get our country going in the right direction.” ― Nevada woman, age 58

“She demonstrated how a good prosecutor has the skills to communicate powerfully. Her story is very compelling.” ― New York man, age 72

“She focused on the question at hand and spoke on the issues in a concise, direct, clearly well-informed way. She also showed strength, character, personality, and a confident path to the solutions she provided.” ― Kentucky woman, age 43

“She remained calm and calmed the stage in a sea of hollering men.” ― Ohio man, age 50

“She smoked Biden like a cheap cigar.” ― Kansas man, age 61

The survey also asked a few questions about Harris’ confrontation with Biden over busing in the second debate. Democratic and Democratic-leaning voters ― including those who didn’t tune into the debates ― said, 49% to 23%, that they trust Harris over Biden to handle racial issues, with the rest unsure or trusting neither. By a smaller margin, 44% to 33%, those voters said it’s more important that children attend schools with students of other races, even if it means busing children some distance from their homes, rather than saying children should attend schools near their homes, even if that means most students are of the same race. (The general American public prioritized local schools over integration, 44% to 30%, according to the same poll.)

How Else Did The Debates Influence Views Of The Candidates?

The debates were voters’ first introduction to many of their prospective nominees and one of their first chances to watch the candidates formally interact. Voters who watched at least clips or highlights of each debate answered questions about whether their opinions of the candidates improved or worsened. This is also an imperfect metric, since people were expected to accurately measure shifts in their own opinions. In reality, voters may have been more inclined to give positive marks to candidates they already liked or vice versa.

But the results suggest that both Warren and Harris impressed a significant share of those Democratic and Democratic-leaning voters who tuned in. Former Housing and Urban Development Secretary Julián Castro also garnered favorable reviews for the first debate. Biden and former U.S. Rep. Beto O’Rourke were among the candidates whose performances turned off more voters than they inspired. Many of the lesser-known candidates failed to make much of an impression one way or the other.