I’m monitoring Pence tonight, and I’ve got to be honest: I don’t know how much he can do to increase his standing in the primary other than hope that other candidates implode. During the last debate, he had plenty of speaking time and, given Trump’s hatred for his former vice president, a pretty strong reception from the Fox News crowd. But still, nothing substantially changed. Voters expected him to give an average performance, and he pretty much delivered. He’s averaging less than 5 percent in national primary polling.

It’s not clear where Pence has room to grow. He’s better known than any candidate on tonight’s debate stage, and voters seem to have decided how they feel about him. If he’s a second-choice to similar candidates — others who, say, share his dislike of Trump but would nonetheless support him in a general election — Pence could benefit from a smaller field. So, the best thing Pence could do might just be to stay the course, continuing to get enough support to appear on a debate stage and waiting out lesser-known and underfunded candidates.

—Analysis by Leah Askarinam

I’ll be monitoring Haley and Christie tonight, who have taken different approaches to arguing for the Republican Party to move beyond Trump. While Haley has been somewhat critical of Trump, Christie has aggressively gone after him. Not coincidentally, Haley remains relatively well-liked among GOP voters, unlike Christie, who is persona non grata to most. I’m interested to see how Haley will seek to balance criticism (indirect or direct) of Trump with efforts to play to base voters, especially in polls of . As for Christie, I’m watching for how other candidates will use him as a foil to demonstrate their pro-Trump bona fides.

—Analysis by Geoffrey Skelley

I’m watching Burgum and Scott tonight. Their task is pretty simple: Get Republican voters to notice them. According to the poll we conducted before the debate with Ipsos and The Washington Post, they’re the two most anonymous candidates on that debate stage tonight (as measured by the share of Republicans who don’t have either a favorable or unfavorable view of them). If they’re going to change that, they need to really get in the middle of some exchanges and emerge from the debate as one of the top storylines.

—Analysis by Nathaniel Rakich

At PolitiFact, this is our fifth presidential cycle. We’ve published more than 23,000 fact-checks since launching in 2007, all using our Truth-O-Meter, which rates claims on a scale from “True” to “Pants on Fire” false.

If PolitiFact is new to you, there are a couple of rules of the road. First, we don’t fact-check every claim every candidate says. We couldn’t … we’d be dead. We focus on claims that are particularly interesting, in the news or obviously potentially wrong. Our grading scale tries to measure both the literal truth and how voters might interpret a politicians’ words. So if Pence tonight claims that he and Trump “achieved energy independence” in their first three years of office, it can be more complicated to fact-check than you think.

In Pence’s case, yes, the United States did produce more energy than its citizens consumed during the Trump-Pence administration, but that was built on more than a decade of improvements in shale oil and gas production, as well as renewables. And the U.S. did not produce more gasoline than it consumes (which is maybe what you were thinking about). And if that’s not enough, even though the U.S. didn’t use all the energy it produced, it still imported a substantial amount of energy to serve domestic markets.

So far in this cycle, we’ve published more than 50 fact-checks of the GOP candidates. Our checks tend to follow the polling of the race. We'll be drawing on those previous fact-checks, as well as the thousands of other claims we've vetted, throughout the night.
—Aaron Sharockman, PolitiFact

Abortion was a big topic in last month’s debate, so we asked about it specifically in this month’s pre-debate 538/Washington Post/Ipsos poll. We asked if a new federal law banning abortion after six weeks of pregnancy except in the case of rape, incest, or when the mother's life is in danger, to which 57 percent of likely Republican primary voters said that they’d support the policy and 36 percent said they’d oppose it (8 percent didn’t know or skipped the question).

However, when we asked who they think should make the decision whether a woman can have an abortion, 54 percent said the decision should be left to the woman and her doctor, while 44 percent said abortion should be regulated by law.

—Analysis by Holly Fuong of 538