Across the rest of the nation, attitudes about guns appear to be changing.

A CNN/ORC International poll released Wednesday indicates that a slight majority now favor major restrictions on owning guns or an outright ban on gun ownership by ordinary citizens and more than six in 10 favor a ban on semi-automatic assault rifles.

The number of Americans who favor major restrictions or an outright ban has typically hovered just under the 50% mark in recent years; now that number is 52%. That's a rise in 5 percentage points from a CNN survey conducted in August following the mass shootings at a movie theater in suburban Denver that left 12 dead and shootings at a Sikh temple in suburban Milwaukee, where six people were killed. The 5-point rise is within the poll's sampling error.

Forty-three percent said the elementary school shootings in Connecticut make them more likely to support gun control laws, a 15-point increase from January 2011 following the Arizona gun rampage that wounded U.S. Rep. Gabrielle Giffords. Half of those questioned said the school shootings have not changed their opinions on gun control, down 19 points from January 2011.

But that's just roughly half of the country.

The other half is made up of the kind of people who have flooded Klein's suburban Washington shop after the Newtown shootings. People who, like Klein, believe that if Sandy Hook Elementary School teachers were armed, they would have been able to kill the shooter before he killed all those children.

"Last night I didn't get out until 10," Klein said through a mouthful of a rushed lunch.

He's almost sold out of AR-15s, he said. He just sold two Wednesday morning to a man who wanted them for his sons.

Since the gun sales are not reported, trends in gun sales are typically tracked by the number of background checks the FBI conducts each year. In 2011 -- a record year -- the FBI conducted 16,454,951 background checks. In 2012, not counting the month of December, the FBI has already conducted 16,808,538. This includes the run on guns after Obama's re-election but does not include the recent sprint to buy up weapons after the Newtown shootings.

And Klein's store's sales are not an anomaly; gun stores across the country are reporting record sales in the week following the Newtown shootings. Klein said gun owners are worried they won't be able to purchase semi-automatic rifles such as the AR-15 in the future, so they are buying them up now.

Those concerns are rooted in the fear that tampering with Second Amendment rights could lead to a slippery slope of infringing on other constitutional rights, gun policy experts said.

"With respect to assault rifles, I have a constitutional right to have one. ... That's what our founding father and mothers recognized," said Feldman of the Independent Firearm Owners Association. "It's what it protects us from -- the possibility of a tyrannical government.

"I don't think we're going to have a tyrannical government, and I don't think Obama (is going to bring about a) tyrannical government. If we take away the Second Amendment, maybe it would."