The backlash against Senator Kelly Ayotte (R-NH) for her vote to block the expansion of gun sale background checks is intensifying as the senator returns home to face voters in the Granite State.

At a town hall meeting with constituents in Warren, New Hampshire on Tuesday, Ayotte was angrily confronted by Erica Lafferty, whose mother was killed in the Newtown massacre.

“You had mentioned that day the burden on owners of gun stores that the expanded background checks would harm,” Lafferty said, referring to the day that Ayotte voted against the Manchin-Toomey compromise bill to expand background checks.

“I am just wondering why the burden of my mother being gunned down in the halls of her elementary school isn’t more important than that,” Lafferty asked. Her mother, Dawn Hochsprung, was the principal of Sandy Hook Elementary School, and was shot and killed in the attack.

Ayotte responded haltingly, saying “I’m obviously so sorry…and, um, I think that ultimately when we look at what happened in Sandy Hook, I understand that’s what drove this whole discussion — all of us want to make sure that doesn’t happen again.”

Ayotte went on to explain that she didn’t believe that expanded background checks would have prevented the shooting.

Video of the exchange is below, via NBC News:

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Later in the day, a town hall in Tilton, New Hampshire, devolved into a shouting match when Lafferty walked out in frustration after Ayotte moved on from a gun safety question to discuss the September, 2012 attack on the American diplomatic mission in Benghazi, Libya.

Ayotte has become a top target for gun reform advocates since her “no” vote on the Manchin-Toomey background check compromise bill. Americans for Responsible Solutions — the pro-gun-reform group led by former congresswoman Gabrielle Giffords and her husband Mark Kelly — has been running radio ads throughout New Hampshire ripping her for ignoring the 89 percent of New Hampshire voters who support expanding background checks, and Ayotte’s approval rating has plunged a net 15 percent in the wake of her vote.

If Ayotte seeks re-election, she would face New Hampshire voters in 2016.