Federal law-enforcement officials cautioned that gun sales were extremely volatile. Nationally, rifle and handgun sales surged 17 percent, for example, in May, compared with May 2007, according to Federal Bureau of Investigation figures. That was before Mr. Obama had clinched the Democratic nomination. Sales then fell and were essentially flat by September compared with the year before, even as the campaign heated up, before rising 14 percent in October. November figures were not yet available.

What is clear is that every gun seller  not to mention every advocacy group for gun ownership that depends on dues-paying members  has an incentive to stoke the concern that can prompt a gun sale. Political uncertainty, gun dealers say, is great for business.

“Clinton was the best gun salesman the gun manufacturers ever had,” said Rick Gray, owner of the Accuracy Gun Shop in Las Vegas. “Obama’s going to be right up there with him.”

Sales at his shop doubled on Wednesday, Mr. Gray said, to more than 20 guns from three to 10 on a typical day.

Asked if that made him root for Democratic candidates, Mr. Gray said no. “It’s not all about profits; it’s about what’s he going to do for the country,” he said, noting that he had supported Senator John McCain, who was the Republican nominee.

A National Rifle Association spokesman, Wayne LaPierre, dismissed the notion that the group had any incentive to increase gun sales or membership. “Ridiculous,” Mr. LaPierre said. “I hope President-elect Obama keeps his promises and protects gun rights. If he does that, we’ll be cheering.”

The political battle over guns raged fiercely throughout the campaign in many states where gun ownership is common. On Monday, the day before the election, home-delivered copies of The Pittsburgh Post-Gazette arrived in plastic bags that said, “Vote Freedom First” and “Defend Freedom  Defeat Obama.” The bags were paid for by the N.R.A., whose initials were printed on each one.