(CNN) - The National Rifle Association has been known as one of Washington's most powerful lobbies.
But some of the organization’s opponents have questioned whether the NRA holds the power it once did.
If they’re right, lawmakers who vote against the group in support of an assault weapons ban or other legislation may have less of a political price to pay for their vote.
NRA president David Keene said Thursday in an interview on CNN’s “The Situation Room” that the group, like others, makes intentional decisions about where to spend its cash and wield its clout.
“When we get into a political season, we're like everybody else - we look at where we can maximize our influence, where our people that we support are, and where the people that we oppose are,” Keene said.
He was presented data from this year’s Senate elections compiled by the Center for Responsive Politics. The information showed that the NRA spent more than $4 million on Senate races but lost seven of the eight contests in which it invested more than $100,000.
“Those races weren't decided on Second Amendment issues,” Keene said. “When we have a race in which there is a candidate who is very clear on the Second Amendment and one who is opposed to it and that becomes an issue, then gun owners and believers in the Second Amendment go out and vote that issue.”
A better example of the organization’s power would be last year’s gubernatorial recall election in Wisconsin, he said. An effort to recall Gov. Scott Walker that received national attention failed in June.
The NRA’s influence, he said, is derived of “the gun owners that look to us for leadership.”
Several Democratic senators have questioned the group’s influence.
Sen. Chuck Schumer, D-New York, told The Huffington Post on Friday that the NRA is a “fringe group” and "doesn't even represent average gun holders."
Sen. Chris Murphy, who represented Newtown, Connecticut, in the U.S. House at the time of the December 14 school shooting massacre, said Tuesday on CNN’s “Piers Morgan Tonight” that “they're much less successful than they used to be.”
“In fact, you'd be better off being against the NRA in the 2012 elections than you would be being with them and that was even before Newtown happened,” Murphy said.
“So I just think that we need to wake members up to the fact that if they want to do the right thing here and join us on common sense gun reform there's not really a political price to pay at the hands of the NRA like there may have been a decade or two ago,” the Democrat said.
Keene said in the interview that he and members of his family have received death threats which has illustrated to him "the incivility of political discourse at some levels in this country."
- CNN’s Joe Johns and Carol Cratty contributed to this report