Guide to gun legislation on Capitol Hill Tuesday

Sandy Hook families come to the Capitol today to press senators for tougher gun measures.

We expect them to stick to the Senate side and meet with senators who oppose enhanced gun laws or moderate Democrats who may have trouble voting for a gun bill.

There is a conference call this afternoon with those families.

From a parliamentary standpoint, the Senate is NOT on the gun bill. That's because they are stuck on the "motion to proceed" to the actual bill, due to a threatened GOP filibuster. In other words, Senate Majority Leader Harry Reid, D-Nev., would need to cobble together 60 votes just to formally LAUNCH the debate and get cloture, and then another 60 votes to end debate.

So, we'll hear a lot about guns on the floor today. But they are technically not on the bill.

Reid has not yet filed cloture on the motion to proceed. He could do that today. And even so, that typically takes TWO DAYS from when he has filed cloture just to get to that vote. So that means Thursday is most likely for the first big procedural vote on guns.

That said, Democrats will probably pick up a couple of their moderate-to-conservative Democrats who face tough re-elections next year -- but lose a few, too. That means they need some Republicans to vote for cloture.

Don't forget: President Obama is having dinner Wednesday night with 11 Republicans senators. If a big vote is pending Thursday, he could really use that meal to apply pressure to vote for cloture Thursday.