Washington Post-ABC News Poll April 11-14, 2013: "Would you support or oppose a law requiring background checks on people buying guns at gun shows or online?" Support: 86 percent. Oppose: 13 percent.
Even if this figure is close to accurate, it doesn't really matter if the intensity isn't there. As many have pointed out, people who support gun rights care very strongly about this issue 24/7/365 while the majority of those who support more gun laws don't care much about the issue at all and usually only immediately following a major tragedy. Gun rights supporters are a powerful block and they'll easily vote against any politician who threatens these rights even if they agree with them on everything else.
the left-leaning Daily Beast summed it up pretty well in a recent article, Why the President Lost on Gun Control
The New Republic article mentioned in Daily Beast.
http://www.newrepublic.com/article/112946/gun-control-failure-2013-who-responsible#
I had wondered about that 90% stat. Seems it was 86% in a poll that over sampled Dems by 10% and under sampled gun owners by maybe 20%. Over half of the house holds polled had no firearm. Here in Texas I don’t know of a single house hold in my area that does not have firearms.
My guess is the poll sample was all NE states...