Moderators lose control of argument between Christie and DeSantis

• "The question was very direct, is he fit to be president or isn't he," Christie said. "The rest of the speech ... [is] completely non-responsive."
• "Ron, is he fit or isn't he?" Christie repeatedly asked DeSantis.
• Moderators tried to interject multiple times to end the exchange, but the two candidates yelled over them.

DeSantis said that there is an opportunity to choose somebody "who is in the prime of their life" for president.

• "We have an opportunity to nominate someone and elect someone for two terms who's going to be spitting nails on day one and for eight years deliver you big results."
• "We should not nominate someone who is almost 80-years-old," DeSantis said.

The big picture: Trump would be the oldest president inaugurated if he wins in 2024, and rivals have highlighted gaffes by the former president to raise questions about his mental fitness for office.

• Polling also shows that the ages and mental fitness of the two leading presidential candidates — Trump and President Biden — have emerged as a concern for voters.

Zoom in: Christie, a vocal Trump critic, repeatedly criticized the former president on stage during the debate hosted by NewsNation, while the other GOP rivals largely avoided direct criticisms.

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