The Napa Valley Register reported before the event started "55 people had signed up to speak, and the forum ran over its allotted time of an hour and a half." Other reporters on the ground noted an overflow crowd of 200 spilled into the hallways.
The last time crowds like that showed up to talk about a contentious issue with a congressman was during the health care fight, when members -- including Thompson -- were shouted down by the nascent tea party. This time, the reported tone was more respectful, and it wasn't just conservatives doing the talking.
KGO-TV reported the atmosphere was "tense" but noted that both sides spoke at length at the town hall.
"It's not the guns that kill people," an area firearms instructor said, according to the Register. "A magazine has never killed anybody either. If you're mentally ill and you're going to kill somebody, you're going to kill somebody."
Sentiments like that were met with passionate rebuttals.
"I know I'm going to get booed, but when I listen to the leadership of the NRA saying we need more guns in the schools, I could vomit," a local woman said, according to KGO.
Thompson has two more gun violence town halls to go back home before he returns to Washington and begins setting up hearings on the problem that could come near the end of the month. Those meetings are likely to draw a public eager to talk about guns -- but if the the Napa town hall is any indication, it will be both sides that show up with fire in their bellies after Newtown.
Here's KGO's report on the Napa meeting: