Senators Joe Manchin (D-WV) and Pat Toomey (R-PA) have reached a deal allowing for background checks on gun sales online and at gun shows, NBC News reported Wednesday morning.

The agreement, reportedly reached late Tuesday night, would also include exemptions for gun sales between family members, and will be announced Wednesday.

Some sections of the deal were reportedly passed along to the National Rifle Association (NRA), which has been loudly lobbying against the expansion of background checks amid calls for tighter gun safety legislation in the wake of the December 2012 mass shooting at Sandy Hook Elementary in Connecticut. Both lawmakers have received an "A" rating from the group for their voting record on gun-related legislation.

The announcement would come a day before Senate Democrats were set to bring the issue up for debate, in spite of a divide between their Republican colleagues on whether to filibuster any attempts to do so. While 13 GOP senators, including Senate Minority Leader Mitch McConnell (R-KY) have promised to join in on a filibuster, others, like Sen. John McCain (R-AZ), have criticized the idea.

"I don't understand it," McCain said in an interview with CBS News on Sunday. "The purpose of the United States senate is to debate and to vote and to let the people know where we stand."

The Wall Street Journal also criticized the filibuster threat in an editorial on Tuesday, saying it allowed President Barack Obama the leeway to label the GOP as being full of obstructionists, which pressures moderate party members.

"The President's calculation seems to be that even if gun control fails, at least he'll have a keep-kids-safe political issue to help flip the House back to Democratic control in the next midterm," the Journal said. "In that sense his inflammatory rhetoric is meant to bait Republicans, some of whom are biting."

[Image by Flickr user gordontarpley, via Creative Commons]