A more powerful reason might be that we're in the midst of a surprisingly heated presidential race, in which things like abortion and gun control are naturally going to be debated and considered.
It also helps that there are few better surrogates for our country's partisan differences than the NRA and Planned Parenthood.
In a survey conducted in July, NBC and its partner the Wall Street Journal found that the two organizations were the most popular political entities in the country. The NRA is viewed positively by 43 percent of Americans; Planned Parenthood by 45 percent. The net positive ratings for each (positive minus negative) were plus-11 and plus-15, respectively.
That's higher than the Supreme Court (39 percent positive, plus-7) and the highest-rated politician, Bernie Sanders (24 percent positive, plus-5).
But it's not because both organizations are universally beloved. It's because each has strong support from one end of the political spectrum or the other. NBC's Mark Murray provided us with a breakdown of how members of each party viewed the organizations.
Republicans have a plus-54 view of the NRA and a minus-31 view of Planned Parenthood. Democrats view the NRA at minus-31 and Planned Parenthood at plus-59. In other words, these are the most popular organizations in America in part because they are the most partisan -- and independents tend to break favorably for each.
There's another layer of difference that's worth pointing out: gender. Men view the NRA more positively than women, and women view Planned Parenthood more favorably than men.
There's some overlap here with political affiliation, of course. It's also worth noting that men have a net-positive view of Planned Parenthood (plus-5), while women have a net-negative view of the NRA (minus-2).
NBC's pollsters have been asking about the NRA since the 1990s. Over that time, the organization has grown much more popular. In June 1995, 28 percent of Americans viewed the NRA positively. By July of this year, 43 percent held that view.
It's hard to suss out how views of the NRA (and Planned Parenthood) intertwine with partisanship. Is the NRA more popular than it was because Republicans are rallying around it? Is it a function of increased polarization around gun control and abortion? Are the organizations more popular with either party because of increased partisanship, or is something polarizing America and pushing partisans to embrace these organizations? This poll can't answer that question.
As proxies for partisanship in the 2016 election cycle, though, the NRA and Planned Parenthood are just about perfect. There might only be only one better indicator for a person's political position: President Obama, who, the NBC poll showed, is viewed positively by 44 percent of Americans and negatively by 43.