Modest gun reform is finally on the table today in the U.S. Senate, and even though its ultimate fate is uncertain, this much is clear: Republicans are once again warring with themselves.

Ninety percent of Americans support criminal background checks for virtually all gun buyers, but all week long the Senate's GOPers have been squabbling over whether such a reform should even be debated. There is no better example of the chasm that separates Republicans from from the American mainstream.

But wait - as evidenced by all the latest legislative gunplay, we actually have two Republican parties - the one that thrives inside in the conservative cocoon, and the one that wants to be competitive outside the cocoon.

First, the cocooners: Twenty nine Republican senators sought unsuccessfully this morning to suppress all debate on background-check reform - led by tea-partying Ted Cruz, who thinks it's an assault on the Constitution to make it tougher for whack jobs to buy guns. They wanted to kill debate at the outset in part because they saw it as good politics. Republicans will defend 14 Senate seats in the 2014 election - 13 of which are in red states. They deem it a top priority to ally themselves with the gun-fetish absolutists. Their biggest fear is that somebody back home will accuse them of waffling (or, gasp, compromising) and thus mount a right-wing primary challenge.

But there's also a Republican faction that actually wants the party to be nationally competitive again some day. That can't happen if the party stays inside the cocoon. That only happens if the party starts paying more attention to what the American mainstream wants. Which helps to explain why 16 Republican senators thought it was nuts to shut down gun reform debate before it began. They undoubtedly read the polls, saw the landslide support for expanded background checks, and they freaked out - rightly recognizing that debate suppression, in the form of yet another GOP filibuster, would be a disaster for the already tarnished party brand.

Which brings us to Pat Toomey. Clearly he was aware that the tarnished party brand might well doom him in a blue-trending state like Pennsylvania, so this week he took steps to save his own butt. He was a major player in negotiating the bipartisan proposal on background checks - the reform would expand screening to virtually all commercial sales, including gun shows - and for that he deserves praise. But it's worth remembering that politicians will often serve the public interest only when they deem it to be in their self interest.

"Just common sense"

Toomey pulled the rug out from under the filibuster faction because he looked to the future and saw trouble for himself. He won in the tea-party wave of 2010; a midterm electorate is typically older, whiter, and more conservative than it is in a presidential year. But he has to run again in 2016, a presidential year, when a popular Democratic candidate atop the ticket (say, Hillary Clinton) could imperil the prospects of down-ballot Republicans. Toomey can't win again unless he can prod Democratic-leaning swing voters in the populous Philadelphia suburbs to split their tickets on his behalf.

Hence his bipartisan move on guns, and his statement yesterday that expanded criminal background checks are "just common sense." For that, he's getting props from Newtown family members, 33 of whom said today: "(Toomey's) bipartisan compromise to expand background checks will help keep guns from falling into the wrong hands, and most importantly it will help save lives. The senators who have vowed to filibuster this bill should be ashamed of their attempt to silence efforts to prevent the next American tragedy. Their staunch opposition to sensible gun reform is an affront to the 26 innocent children and educators who were murdered in Newtown." The last thing Toomey needed was to be lumped with the GOP obstructionists as a Newtown affronter.

But the legislative journey has barely begun, of course. The Senate has indeed managed to open debate, but we can still expect the obstructionists to do the NRA's bidding - with amendments designed to weaken or kill the background checks - all in the name of Freedom. And they could still try to filibuster the reform prior to its final vote. (Cruz, on a conservative cocoon radio show yesterday: "What should the vote threshold be for legislation that would violate potentially the Bill of Rights? I think it should be a minimum of 60 votes.")

And even if the Senate passes gun reform, it still has to clear the House - which is dominated by Republicans who hail from safe red districts. Those cocooners don't care about the big picture or the party's national brand. In their small world, it's good politics to slavishly serve the NRA, and bad politics to heed what 90 percent of Americans want.

That's the state of our democracy in 2013, for better or worse. To borrow some phrasing from Donald Rumsfeld, you go into battle with the process you have, not the process you might want or wish to have.

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