After the mass shooting in Las Vegas last weekend, guns and gun control are, yet again, topics in Washington. And yet again, most analysts believe that substantial change on the issue seems unlikely.
The reason behind that expected lack of movement is best understood by looking at who owns guns and, critically, who is the most invested in the gun debate.
In total, about 42 percent of Americans households are home to at least one gun, according to data from a June Pew Research Center survey, but firearms aren't spread evenly around the United States.
Men are much more likely to personally own a gun than women, 39 percent to 22 percent respectively. And white households are the most likely to own a gun by far. Nearly half of white households, 49 percent, have at least one gun. Among black households, the figure is only 32 percent. In Hispanic households, the figure is 21 percent.
Geographically speaking, guns are fairly evenly spread across American households, with the exception of the Northeast, where 27% of the households are home to a gun. In the Midwest, 44 percent of homes own at least one gun. In the South, the figure is 45 percent. Out West, it's 46 percent.
That number in the Northeast, which tends to be more densely populated than other regions, may have something to do with the large urban population there. Urban households are far less likely to hold a firearm, only 29 percent do. Among suburban households, the number is 41 percent. And, of course, rural households, close to hunting terrain, are the highest, with 58 percent owning a gun.
The partisan political divide, evident in so much of the U.S. political dialogue, is evident on gun ownership as well. More than half of Republican households, 56 percent, own a gun. In Democratic homes, the figure is only 30 percent.
That's a broad look at ownership and some of those numbers are indeed high, but in most cases, the numbers are below 50 percent. Remember, nationally the figure for households that own a firearm is only 42 percent, according to the Pew data.
And just because a household owns a gun doesn't necessarily mean people in those homes oppose gun control legislation. At least some gun owners favor increased gun regulation - 48 percent of gun owners say they believe in banning "assault-style" weapons, according to the Pew survey.
Taken together, those numbers suggest Congress might be interested in tightening gun laws, particularly after the Las Vegas shooting that killed more than 50 people and left nearly 500 others wounded. Normally a big news event with tragic consequences brings intense pressure on Congress to act. Why are guns different?
One big reason: enthusiasm. Republicans, who tend to support gun rights, seem to care much more about gun policy than Democrats do and by a wide margin.
The August NBC News/Wall Street Journal poll asked, other than foreign policy, national defense, and the economy, which one or two issues "are important enough to you to have an impact on how you vote in an election."
Among Republicans, 45 percent chose "gun rights or gun control" as one such issue. It ranked above immigration at 36 percent and abortion at 26 percent.
For Democrats, only 29 percent rated "gun rights or gun control" as such an issue. That's 16 points lower than the Republican number.
And looking specifically at the 2016 electorate, the divides are even starker. Among those who voted for President Donald Trump, 47 percent said the gun issues were important enough to impact their vote. Among Hillary Clinton voters the figure was 27 percent. That's a 20-point gap.
There is a long list of reasons why tightening gun laws is a difficult task, including lobbying money that supports members of Congress. But when you look closely at the numbers, one side is simply more invested in the debate than the other.
That could change after Las Vegas, but if the 2012 elementary school shootings in Newtown, Connecticut didn't substantially alter the debate, it's fair to wonder how much last week's mass homicide will affect it.
In politics, enthusiasm matters. And on the issue of firearms, gun rights advocates seem to have a crucial edge in that regard.