The attack on the Route 91 Harvest Festival, the Las Vegas massacre killing at least 58 people and injuring over 450 more, opened up debate on the availability of guns. The same questions raised after Columbine, Newtown, and Orlando.

Yet very few changes were made after these mass shooting tragedies. And some laws became more relaxed. In 2004 the federal ban on assault weapons expired. The ban, enacted in 1994, fails repeatedly to be reinstated in Congress.

"This nation often reaches a tipping point, as it did after the near assassination of Ronald Reagan," Senator Richard Blumenthal stated in an interview with PBS Newshour.

...what we need to recognize is that the tipping point comes through awareness and education and continued, persistent advocacy, which is to mobilize people, in the same way the NRA has done."

"The major obstacle to commonsense measures, like background checks and the ban on assault weapons and high-capacity magazines and bump-stocks, and closing a number of the loopholes that enable domestic violence, which is a major cause of death as a result of gun violence, is very simply to break the grip of the NRA."

We must break the grip of the NRA, which will be done through mobilizing the American people."

Democrats cite public opinion polls that show overwhelming support for universal background checks. A national Quinnipiac Poll in June found 94 percent of voters supported background checks on all gun sales. But the measure has failed to get enough Republican support to pass either the Senate or the House.

On Tuesday, Senators Richard Blumenthal and Chris Murphy said "Enough."

In a news conference with the Brady Campaign to Prevent Gun Violence, the Connecticut Senators vowed to draft sensible gun control bills to curb the accessibility of the weapons used in mass shootings.

Sen. Chris Murphy said he’ll reintroduce legislation to strengthen gun background checks, but acknowledged the bill faces long odds in the Republican-controlled Congress.

“We’re going to press hard for change,” Murphy said. “My belief … is that change is likely to come from outside this building.”

Sen. Blumenthal said he'd introduce narrow legislation to close the Charleston loophole, which allows a gun dealer to sell a firearm after three business days even if an FBI background check is incomplete. The loophole used by Dylan Roof allowed him to purchase the gun he used to kill nine people at a Charleston, S.C., church in 2015. Because of the unfinished background check, the gun dealer approved Roof's ineligible purchase.

“Closing these loopholes one by one, making our laws effective one by one, is a way to make our nation safer,” Blumenthal said.

In 2016 the National Rifle Association spent $22,612,663. Of their 2016 political contributions, the NRA reported 1% went to Democrats, 99% went to Republicans.