1. I’ll start it off with the most important budget item you’re going to see in a while: Michael Linden shows that domestic discretionary spending is already, thanks to enacted cuts, scheduled to move to new historic lows. That doesn’t by itself mean that the further cuts House Republicans are demanding are a bad idea — but it certainly means that further cuts cannot be legitimately justified by “runaway” spending.

2. Marco Rubio peddled immigration reform to Rush Limbaugh today and received a pretty warm reception. A good sign for the bill, which depends on whether Republican leaders inside and outside of Congress will close ranks behind it. Rosalind Helderman reports.

3. A key point on immigration from Suzy Khimm: After the demise of Bush-era comprehensive reform, Congress and Obama have pretty much done what that old bill wanted to do on border protection.

4. Meanwhile, Ed Kilgore looks at how solid the Senate bipartisan coalition will be.

5. The four differences between the Senate plan and Barack Obama’s approach, from Adam Serwer.

6. My take on the prospects for immigration legislation.

7. Meanwhile, on guns, this may be a big deal: Paul Ryan apparently supports Obama on background checks. John Rudolf has the story.

8. David Frum: “Good God, there are people in my Twitter feed *condoning* the heckling of a grieving Newtown dad. How can they??” Although, see Erik Wemple for more detail about what actually happened.

9. Very interesting from political scientist Michael Tesler: “How Obama Could Polarize the Gun Control Debate (And Still Help Himself Win).”

10. A nice post from Kevin Drum on GOP attacks on phony targets.

11. The payroll tax cut worked, says Matt Yglesias.

12. And Josh Eidelson looks at “alt-labor” in a post-union world. Interesting