The National Rifle Association says about half a million people have become members since the December 14, 2012, shootings at Sandy Hook Elementary School in Newtown, Connecticut, bringing its numbers to roughly 4.5 million. 

If true, that means (based on 2013 U.S. Census Bureau data) one of every 70 Americans belongs to the NRA. 

That's a lot of people, but there are several much-larger clubs and organizations in the United States: 

• AAA (formerly the American Automobile Association), the nation's leading travel, insurance and automobile association, says it has 53 million members. 
• The AARP (formerly the American Association of Retired Persons), the nation's largest advocacy organization for seniors and retirees, has 40 million.
• The labor group AFL-CIO (American Federation of Labor and Congress of Industrial Organizations) says it has 12.2 million members.
• Warehouse retailer Sam’s Club has more than 10 times as many members as the NRA.
• Financial service group USAA (United Services Automobile Association), which serves American military and their families, has more than 9 million members.
• The Book-of-the-Month Club, the country's oldest and largest book club, has about 8.5 million members.
• The NEA, (National Education Association) the country's largest teachers' union, with 3.2 million members, is smaller than the NRA.