Stuff like background checks barely passed Nevada and failed in Maine in 2016. And those are lean Clinton states. Like OSR has stated before, the polling is one thing but when it comes to votes at the polls it doesn't translate well.
It certainly helps that the NRA is willing to pour millions of dollars (or whatever they can still afford after LaPierre's embezzlement schemes) into disinformation campaigns whenever it comes up on the ballot.
Last year, the National Rifle Association spent more money fighting a push for a universal background check for gun purchases in Nevada than it did on any Senate or House race.
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The gun group poured more than $6.6 million into opposing Question 1, making it the NRA’s second-largest campaign expenditure of 2016. The only contest that drew more funds from the gun-rights group was the presidential election, in which it invested over $30 million in support of Donald Trump.
When Maine voted to defeat the background check proposal, Bloomberg's orgs outspent the NRA six to one.