The term for Lautenberg’s vacant seat runs until November 2014. Christie had two options in how to fill it. Option one: Simply appoint someone to serve out the rest of the term and let voters elect a new senator on schedule next year. Assuming Christie appointed a Republican, that would give the national GOP an extra vote in the Senate for almost 18 months — granted, likely a moderate vote, but that’s still preferable to a liberal Democrat. Maybe the appointee would impress Jerseyans with his Senate record and would stand an incumbent’s fighting chance to hold the seat against Cory Booker next year. Or maybe he wouldn’t intend to run against Booker at all, which would free him up to vote as a conservative for the remainder of the term. Jersey Democrats threatened to sue Christie if he went this route, but as Ed Krayewski noted at Reason, he had cover from the state’s bipartisan Office of Legislative Services. Reportedly, they issued an opinion earlier today stating that the 18-month appointment would be just fine legally.

Option two: Christie could throw all of that away by appointing a very short-term replacement for Lautenberg and scheduling a special election for sometime later this year. That would give Booker all kinds of advantages. Not only wouldn’t he have to face a GOP incumbent with more than a year’s experience in office, he also wouldn’t need to worry about his opponent having lots of time to fundraise. The risk to Christie in choosing this option was that it would bring all sorts of Democratic voters out to the polls on election day who might otherwise have stayed home. And that means Christie, who’s cruising to victory at the moment, could suddenly see his own gubernatorial reelection bid jeopardized by the big surge in Democratic turnout. All of which makes this a no-brainer, right? Appoint a Republican to finish Lautenberg’s term and trust that Christie’s big lead in the gubernatorial race won’t suffer too much for it. How angry could Jersey Democrats be if he appointed a Republican as squishy as he is?

So which option did Christie choose? Option two, of course — except that, in order to protect his own ass electorally, he decided to schedule the Senate special election in October, not on election day in November. Now he gets the best of both worlds, all but handing the seat to Booker ASAP to burnish his “bipartisan” brand while ensuring that he himself doesn’t have to face the extra Democratic voters who’ll turn out to vote for Booker. National Republicans are, as you might imagine, honked off:

The decision to hold a separate special election in October 2013—just two weeks before his own election—would give any interested Republican candidates little time to announce, organize a campaign, and raise the necessary money to take on a top-tier Democrat, likely Newark Mayor Cory Booker…

The governor’s decision, along with growing GOP expectations that his appointee will be a placeholder, means that the GOP’s chance at a pickup now looks like a long shot. But Christie protected his own interests by scheduling a separate 2013 election, ensuring that Booker wouldn’t usher a surge of Democratic voters that could hurt Christie’s November prospects…

“I think this ends his 2016 chances. It’s year after year with this guy,” complained one senior Republican official.

At the Corner, Robert Costa writes, “Insiders tell me that the November 2014 option was advised as the best course of action by national GOP officials, but Christie decided to go his own way.” Of course he did. As always, when there’s a conflict between what’s best for Christie and what’s best for his party, his interests take precedence. His allies are dressing this up, naturally, as the democratic thing to do, but this turn of phrase is revealing:

“Having someone hold that position for 18 months is not the right call,” an ally of Governor Christie told CNN. “It would be against the Christie brand – it’s not who he is, no one should have an appointed elected position for 18 months. People should have a voice and a choice for this.”

The “Christie brand” is, essentially, what the “Bloomberg brand” became in New York City over the course of the last decade: Nominally a Republican but, the better to succeed in a very blue jurisdiction, effectively an independent. (Bloomy eventually became an independent in name too.) The only “good” news in today’s decision is that he chose the course of action that maximizes his own chances of reelection. If you’re excited about a quasi-independent who’s been trending Democratic for the past year getting another term because he still calls himself a Republican, then congratulations, I guess. Also, and needless to say, holding two statewide elections two weeks apart when they could have been held on the same day will cost the state lots of extra money and administrative headaches. You’d think a “fiscal conservative” would pause at that thought but, via the Weekly Standard, here he is throwing his cares about that to the wind in the name of (of course) democracy. Evidently it would have been unconscionable to ask the good people of New Jersey to wait two extra weeks in electing their new senator. When it comes to protecting Christie’s own reelection, spare no expense.