>> But I'm at my wit's end.>> In the wake of Orlando, Senator Chris Murphy seizing the Senate floor and vowing to hold it indefinitely in a shock move aimed at forcing Republicans to back tougher gun laws.>> And I've had enough Of inaction in this body.>> The filibuster unfolding, as Democrats unite in outrage over the fact that Omar Mateen was able to buy weapons despite, once, being on an FBI watchlist.
But Republicans, backed by the NRA, not budging. Reporter Emily Stevenson.>> Democrats generally seem frustrated with this response to mass shooting incidents where we all say our hearts and prayers are with the victims. And we do moments of silence, and there's this period where you're not supposed to talk about politics.
And Democrats have just gotten frustrated with that, and they feel like if you crack down on guns, you can prevent some of these things from happening. And they are trying to take a tougher and more emotional approach from the get go they're saying we need to take action on this issue.
>> This time with 49 dead some cracks showing in a GOP wall. Pennsylvania Senator Pat Toomey in talks on a compromise with a gun control group run by billionaire Michael Bloomberg. And presumptive GOP Donald Trump meeting with the NRA to talk about barring terror suspects from buying weapons.
>> I mean these are pretty familiar talking points and it can be hard to tell whether something is really going to happen. I would say it seems like, just in Washington anyway, there's definitely more pressure on Republicans. It seems like people are more willing to have these conversations, but we have been in this position before.
>> When we don't act, there is a quiet signal that is sent.>> Murphy's home state the site of the 2012 Sandy Hook massacre, and four years and countless shootings later, Democrats hope Mateem's horrific rampage might finally break the impasse.>> And so this isn't new to me.