(NBC NEWS) -- Congress may be away on spring break. But President Obama isn't resting on the issue of guns.
He's invited mothers and victims of gun violence to the White House for an event later today.
Volunteers around the country will initiate a gun-control blitz today calling on Congress to pass stricter laws.
The national day of action comes as Democrats struggle to unify over the issue and Republicans offer new resistance to gun control.
As the Connecticut State's Attorney releases new details from search warrants related to the Sandy Hook shooting tragedy today, supporters of stricter gun laws will hold more than 100 events to push for Universal Background Checks.
Mayors around the country are out with this call for action - "Every person needs to pick up the phone- right now."
There's also a video - Mark Kelly and Gabrielle Giffords demonstrate how easy it is to buy a gun in Arizona.
President Obama will join the all-out offensive with an event later today in the east room...
He'll have a question for congress. He'll want to know which side they're going to be on when it comes to voting on a ban on military- style assault weapons.
Advocates for reform need to topple push back from gun lobbyists. "Criminals aren't going to be checked. They're not going to do this. The shooters in Tucson, in Aurora, in Newtown, they're not going to be checked," said Wayne LaPierre of the National Rifle Association.
Senators have separated the proposed assault weapons ban from a bill seeking universal background checks and stricter penalties for gun trafficking.
Several Republicans including Senators Rand Paul, Ted Cruz, and Mike Lee have already sent the Democratic Majority Leader a letter- promising to oppose any new gun laws.
Senators are expected to vote on the proposed gun bill early next month, right now, its fate is unclear at best.