Jason Roberts, a political science professor at UNC, said the numbers could also be high for Burr and Tillis because of the elections in which they have run.
“I think the primary thing it says is that both those individuals have been in very competitive and very expensive races," he said. "So when you’re in those kinds of races, you’re going to attract more support from groups of people who are on your side.”
Roberts said these statistics are not surprising because Burr and Tillis are already supporters of the Second Amendment.
“Burr and Tillis are people with strong voting records on gun rights, so there’s nothing surprising about that at all,” he said. “Plus the research on this shows that groups like the NRA are giving money to people who are generally already supporting their positions.”
Bryner said interest in these numbers has increased after the shooting in Las Vegas on Oct. 1, and that this usually happens after similar events.
“We see a lot of interest in this issue after major tragedies, and we just try to make sure that our data is up to date so that people can find what they need to know to understand how they might be able to make a change,” she said.
The NRA released a statement in the aftermath of the Las Vegas shooting urging lawmakers to regulate bump fire stocks, which are what the shooter put on his weapon to make it automatic.
“The NRA believes that devices designed to allow semi-automatic rifles to function like fully-automatic rifles should be subject to additional regulations,” the NRA said.
The NRA emphasized in the statement that it aims to keep Americans safe.
“In an increasingly dangerous world, the NRA remains focused on our mission: strengthening Americans' Second Amendment freedom to defend themselves, their families and their communities,” it said.
Bryner said constituents should pay attention to future votes on gun issues, as large amounts of funding from one particular group raises questions about how it will affect the recipients' policy positions going forward.
“I think that there might be a vote fairly soon on these adjustments to guns that make them automatic," she said. "And I’d be watching Burr and Tillis carefully to see how they vote on that, to see what the NRA says about that and to see if the senators are accountable to the people or to the moneyed sources that help them win."