Donald Trump turned the Republican presidential debates into high-rated TV spectacles. But the fate of his campaign for the nomination may be decided by a far more intimate televised forum.

The town hall — in which a candidate typically has a one-on-one exchange with an anchor and takes questions from voters — has become an increasingly popular format on cable news networks. There have already been 24 of them across CNN, Fox News and MSNBC; there were just a few in the 2012 campaign.

While town halls don’t deliver the same big Nielsen numbers as the debates, they deliver solid ratings and give TV news a chance to drill deeper into the candidates’ policy positions.

The programs also help mitigate ongoing charges by some critics that TV news is giving the media-friendly Trump too much free airtime and has not subjected him to enough rigorous questioning.

The Republican front-runner had the rockiest week of an otherwise successful campaign largely because of his answer to a question from MSNBC’s Chris Matthews during a Wednesday town hall. Matthews asked if a woman should be punished for having an abortion if the procedure became illegal. Trump said yes, but then revised his position after an outcry from both abortion rights activists and abortion opponents. He has been dogged by the statement ever since.

“A debate is like three-dimensional chess or a simple knife fight,” CNN’s Anderson Cooper said. “You have people competing against each other with very strict but clear cut parameters on the time they have for responses. The town hall allows you to have a conversation with the candidate.”

When Trump gets offered an hour of prime time for a town hall appearance, so do his Republican rivals, which has helped level the playing field. Trump’s town halls provide the highest ratings: his appearance with Matthews attracted 1.69 million viewers. A session with Cooper on CNN had 4 million viewers Tuesday, the highest-rated so far. Trump has appeared more frequently, but that has to do with his willingness to go on camera.

What helps distinguish the town hall from other TV campaign coverage is the participation of the audience. “It’s a rare time in the campaign when the questions come from the voters and not us,” said CNN Washington bureau chief Sam Feist.

While Matthews questioned Trump on his abortion stance, the first question about it came from a University of Wisconsin at Green Bay student in the audience.

“You never know what’s going to bring out something,” said MSNBC President Phil Griffin. “She asked a pretty simple question. “

Variations of the town hall have been around presidential campaign coverage for decades. Two of the executives who run cable networks — Fox News Channel Chairman and CEO Roger Ailes and CNN President Jeff Zucker — both played roles in developing the format.

Ailes was a young television producer when he was hired to handle the media for Richard Nixon’s 1968 presidential campaign. He designed what became known as the “Man in the Arena” shows in which Nixon took questions from a sampling of voters in cities where the programs were taped with a studio audience of supporters. It was a way to present Nixon’s policies while making him look more comfortable among regular people.

In 1992, Zucker, then executive producer of “Today,” had third-party candidate Ross Perot appear for one or two hours to take questions from viewers who called into the morning program. His Democratic opponent, Bill Clinton, followed suit.

“What we’re doing today — it’s the exact playbook of what we were doing in 1992 on the ‘Today’ show,” Zucker said.