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The Senate's failure to end a filibuster of stronger gun legislation yesterday prompted the president to lash out against the "continued distortion of Senate rules" that allows 41 senators to block the will of their 59 counterparts. The problem is even more stark when you consider the population those senators could represent: Just over ten percent of Americans can block any federal legislation from moving forward. That's fewer people than live in the state of California alone.

A Senate filibuster, as it is commonly practiced, allows any senator to speak indefinitely on any bill. If 60 of his or her colleagues vote to end the filibuster (known as "cloture"), the legislation can move forward. If not, it's essentially defunct. We compiled data comparing state population, yesterday's Senate vote, and the 2012 election to put together a portrait of how senators representing only a fraction of the country could ensure that no bill advances.

States, by population

First, we looked at each state's population, using July 2012 population estimates from Wikipedia. The darker the blue, the higher the population.

The twenty-one smallest states

Then we isolated the 21 smallest states. If every senator from each of these states were to oppose cloture on any given bill, they could maintain the filibuster indefinitely.

Those states have a population of about 32 million Americans — which is just over ten percent of the country. And about six million fewer than live in California.

Vote to end the filibuster of background check compromise

In practice, it's not only the smallest states that will support a filibuster. After all, a number of them, particularly in the Northeast, are "blue" states. Here's how the 2012 vote broke down. Blue states voted for Obama; red, for Romney.

And here's how states voted on the Manchin-Toomey compromise. Dark blue states had two senators supporting cloture. Lighter blue states had one.

It may be easier to see how those states compare in this GIF. For the GIF, the map above is reversed: darker colors mean more senators backing cloture.

Breaking out the population of the states that backed the filibuster (and splitting it in half if only one senator backed cloture), we see that 37.7 percent of America, represented by 46 senators, blocked the background check compromise.

It's also worth comparing that to the Washington Post's recent poll on the topic. The poll asked: "Would you support or oppose a law requiring background checks on people buying guns at gun shows or online?" Yielding the following responses:

Eighty-six percent of Americans backed background check reform. Senators representing 38 percent of America blocked it. But it only takes senators representing ten percent of America to block any federal policy whatsoever.

This article is from the archive of our partner The Wire.

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