DeSantis wouldn’t directly answer when the moderators asked him if he would sign a national abortion ban, and Pence pounced. He comes from the social conservative wing of the party, and supports a national ban. This isn’t the first time Pence has criticized DeSantis for not being conservative enough on abortion, either.
-Analysis by Nathaniel Rakich of FiveThirtyEight

Haley reiterated her calls for "compassion" when the country debates abortion, though she declined to state whether she would support a federal ban on the procedure.

Haley noted the uphill climb to a federal ban, referencing the 60-vote filibuster in the Senate, but said she would oppose late-term abortions and punishments for women who receive abortions.

"Can't we all agree that we should ban late term abortions? Can't we all agree that we should encourage adoptions? Can't we all agree that doctors and nurses who don't believe in abortion shouldn't have to perform them? Can't we all agree that contraception should be available? And can't we all agree that we are not going to put a woman in jail or give her the death penalty if she gets an abortion? Let's treat this like the like the respectful issue that it is," she said.

-ABC News' Tal Axelrod

The candidates are now debating abortion, which has obviously been a hot-button issue lately, but it’s actually not super important to Republican primary voters right now. According to our FiveThirtyEight/Washington Post/Ipsos poll, only 6 percent of Republicans identified limiting abortion as one of their top three issues.
-Analysis by Nathaniel Rakich of FiveThirtyEight

In the commercial break we get an ad targeting pro-Ukraine Republicans from Defending Democracy Together, a PAC led by a group of anti-Trump conservatives who have been very active in politics since 2017. In a poll from the Pew Research Center in June 44 percent of Republicans said the US was giving too much aid to Ukraine. I'm not sure how much this ad is going to register; Ukraine and national defense barely register in polls of Americans' most important problem these days. I think it says more about the divide in the party over Trump — who hasn't been mentioned in the debate at all so far.
-Analysis by G Elliott Morris of FiveThirtyEight

In the aftermath of a debate, it can be hard to figure out the actual impact of a viral moment or heated exchange. Here are some data-driven approaches that can help cut through the noise:

First, ignore “instant polls” that ask questions only among people who watched the debate. That group is not likely to represent the feelings of the broader population. Instead, look for post-debate polls — (like ours with Ipsos and the Washington Post) — that ask questions among the same group of Americans both pre- and post-debate.

Second, in the days following the debate, look at data that captures attention to candidates, such as trends in search results or media coverage, to determine which candidate made the biggest splash. Media attention is crucial for candidates who aren’t well known to gain traction in the polls and with donors.

Finally, look for changes in horse-race polls in the week or two after the debate. There is a lot of noise in primary polls (especially this time around) and it can take some time for changes in public opinion to be reflected in our polling average.

The big thing to remember is that what’s important to journalists and television pundits may not be what’s important to the public, and we have to wait for pollsters to ask them how they feel.

-Analysis by G. Elliott Morris of FiveThirtyEight