Hillary Clinton's latest ad in the key early primary states of Iowa and New Hampshire focuses squarely on gun control, an issue that separates the former secretary of state from her closest Democratic challenger, Vermont Sen. Bernie Sanders.

In the 30-second spot, titled "Together," Clinton addresses the controversial subject as she speaks to a crowd at an Oct. 5 town hall in Manchester, New Hampshire.

"This epidemic of gun violence knows no boundaries. Between 88 and 92 people a day are killed by guns. We're better than this. We need to close the loopholes and support universal background checks," Clinton says in the commercial. "How many people have to die before we actually act, before we come together as a nation?"

According to the Washington Post, gun control marks Clinton's "greatest difference with Sanders," and her campaign has sought to highlight the Vermont senator's mixed record on the issue, especially with respect to background checks.

Sanders has voted against the Brady background check law and other gun-control measures. Clinton, however, does not mention her rival by name in the new spots, which are part of a $6 million ad buy in the Hawkeye and Granite states.

Clinton has been outspoken in her criticism of the National Rifle Association (NRA) and other pro-gun entities on the campaign trail, an approach Politico reported plays well with the Democratic base. When the former first lady embarked on her first presidential bid in 2008, on the other hand, she had stayed largely silent on the issue.

Then a New York senator, Clinton in fact had criticized rival Barack Obama for what she called his "elitist" and "out of touch" comments that some Pennsylvanians are "bitter, they cling to their guns."

But days after a gunman killed nine people and wounded another nine at Umpqua Community College in Roseburg, Oregon, this year, she announced her plan to curb gun violence and said she wanted to build a national movement to counter the influence of the NRA.

Watch the ad: