Story highlights Joe McLean: The NRA has bought many elections with massive spending

McLean: But Americans are finally fed up and seem to be cooling toward the NRA

He says some senators who voted down background checks saw a hit in approval ratings

McLean: More politicians may change their minds if they lose support for opposing gun control

On Wednesday, former President Bill Clinton delivered the first of a series of lectures on public service at his alma mater, Georgetown University. When questioned by a student on the failure of the legislation on gun background check in the Senate, Clinton spoke in parables.

"You know that old story about, the problem with a cat that sits on a hot stove is that cat will never sit on a hot stove again, but also it will never sit on a cold stove. I think this is a cold stove," Clinton mused.

Like most parables, the message was clear. For the past 30 years, the NRA has bought many elections with massive spending and grass-roots campaigns. No candidate who has ever been scorched on the NRA's stove wants to get burned again, so they cower in the corner. Politicians quake in fear whenever CEO Wayne LaPierre threatens hellfire and brimstone upon any apostate with the temerity to question the NRA's gospel of the gun.

But America is finally fed up. New surveys by Public Policy Polling and Quinnipiac University confirm Clinton's view that the public has cooled to the NRA.

Joe McLean

Several senators who voted against background checks have taken hits in their approval ratings . From February to April, Alaska Sen. Lisa Murkowski's overall approval rating dropped 8%. In Ohio, Sen. Rob Portman's rating went down 9% since October. And Sen. Dean Heller of Nevada saw his rating go down 3% since October/November. Alarmingly, for the NRA, this show of disapproval is happening in red states that should be gun rights strongholds.

Being on the wrong side of history can be painful. Today's more tea-flavored GOP politicians find themselves badly positioned on guns. Their ideological rigidity on immigration reform, marriage equality, reproductive rights, Wall Street reform and numerous other hot-button issues is unpopular.

When you factor in the outrage over gun violence, Republicans -- who seem inextricably bound to the NRA in the public's mind -- are under the gun.

This week, in a town hall meeting, New Hampshire Republican Sen. Kelly Ayotte, who voted down background checks, was confronted by the new political reality up close and personal. Erica Lafferty, whose mother, Dawn Hochsprung, was the principal at Sandy Hook and among the first to be gunned down, asked Ayotte , "You had mentioned that day the burden on owners of gun stores that the expanded background checks would harm. I am just wondering why the burden of my mother being gunned down in the halls of her elementary school isn't more important than that."

Ayotte defended her vote. But questions like the one Lafferty asked won't go away.

We will see how the gun issue plays out on the national stage in the coming months. If senators lose support because they refuse to give way to some gun control regulations, we may see some changes of heart.

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This has certainly been the case in the debate over immigration reform. Senate Majority Leader Harry Reid has promised to bring the matter to the floor again in light of the popular support for immigration reform. It's possible that we may even see a background check bill come back to the Senate later in the year. Of course, the gerrymandered House is quite another matter.

So finally, the heat may be on the NRA for a change. And for the senators who voted against background checks, it looks like they've jumped out of the frying pan and into the fire.

As usual, Bill Clinton saw it coming.