Christie criticized the idea that the president could cozy up to Vladimir Putin, noting that all recent presidents have failed to engage Putin by not being tough enough. He then hit Trump for having said that Putin was "brilliant and a great leader." As the night has worn on, Christie continues to be really the only candidate who is bothering to attack the guy who is 40 or more points ahead of every other candidate in national GOP primary polls.

— Analysis by Geoffrey Skelley of 538

Ilia Calderón is asking about sending U.S. troops to Mexico. In a late August/early September survey by Morning Consult, 41 percent of Republicans said they thought that sending U.S. troops to fight cartels in Mexico would be “very effective” at limiting the supply of illegal drugs in the United States. Other strategies had more support among Republicans, such as sending more resources to the U.S.-Mexico border (54 percent), empowering U.S. law enforcement to combat opioids (45 percent), and punishing drug violators in the United States (43 percent).
—Analysis by 538

Haley going after Ramaswamy was a recurring theme in the first debate. They were the standout candidates in our polling last time and there was a lot of speculation about Ramaswamy moving up in the polls — perhaps even surpassing DeSantis. But since August, Ramaswamy has actually lost support, to the point where Haley passed him in our polling average today. It makes sense that they're trading blows again; this seems to be a successful strategy for Haley, and Ramaswamy can't help but take the bait.
-Analysis by G. Elliott Morris of 538

The candidates are discussing support for Ukraine. About half (49 percent) of Republicans and Republican-leaning independents say that vital U.S. interests are not really at stake in the war in Ukraine, according to an August Echelon Insights survey. Thirty-seven percent disagree, saying that if Russia wins, vital U.S. interests and values are threatened. Fourteen percent are unsure.
—Analysis by 538

Trump maintains a lead of 33 percentage points over Haley, his nearest competitor in New Hampshire, according to the most recent polls. Haley appears to have benefitted the most from the first debate in the state, gaining 8 points compared to her average result on Aug. 23. No other candidate’s average has moved by more than 3 points, either up or down.

According to a September survey from the University of New Hampshire/CNN, only 36 percent of likely New Hampshire primary voters have definitely decided who they plan to vote for. Thirty-eight percent said they are leaning toward someone, and 24 percent said they are still trying to decide. Trump’s voters, however, were much more firm on their choice: Sixty-nine percent said they have definitely decided, compared with 31 percent for Ramaswamy and less than 20 percent for the other candidates.

When it comes to policy, New Hampshire Republican primary voters seem particularly concerned about economic issues, according to a September survey by NMB Research for the Competitiveness Coalition and the Josiah Bartlett Center for Public Policy. Given a list of issues that have been raised in the primary, 32 percent said the most important issue to them would be reducing federal budget deficits by cutting spending; 21 percent said it would be spending less on green energy by repealing parts of the Inflation Reduction Act; and 18 percent said it would be keeping taxes low. The only other issue to reach double-digit support was deploying the U.S. military to the Mexican border to stop illegal drugs from entering the country, which was named as most important by 19 percent of voters.

—Analysis by 538