A little over a week ago, Cory Booker told CBS’ Face the Nation that he was considering a run against Chris Christie in next year’s New Jersey gubernatorial election, while offering a few qualifications on commitment to it.  “I’ve got to… be a part of my party’s push forward,” Booker told Bob Schieffer, “whether it’s me as a candidate, or supporting other candidates for that office.”  On the other hand, Booker also said, “I’m actually looking at [a Senate candidacy] a lot as well.”

Last night, the Wall Street Journal reported that Booker seems to be aiming now for the latter:

Newark Mayor Cory Booker is leaning against jumping into next year’s race for New Jersey governor and instead is having serious discussions about running for the U.S. Senate in 2014, according to three people familiar with the matter.

The Democrat has discussed announcing later this week that he will form an exploratory committee focused on a run for the seat held by the 88-year-old Democratic Sen. Frank Lautenberg, two of those people said. It is possible that Mr. Booker, a prolific Twitter user, could make the announcement via a message to his 1.3 million followers.

“He’s got an intricate system of who he’s going to call before he tweets this,” one of the people said.

This probably has to do with Christie’s standing in New Jersey after Hurricane Sandy.  His approval rating soared after the disaster, and he gained ground even with Democrats after his public cooperation with Barack Obama on the federal response.  Both his popularity and approval rating with New Jersey residents have far exceeded re-elect numbers with just about a year to go before the election.  No one is unbeatable in theory — remember what happened to George H. W. Bush’s high approval ratings 18 months before the 1992 presidential election — but Christie would be as close as one gets to it at the moment.

Waiting for the 2014 race makes more sense for Booker.  First, he hasn’t prepared a real organization to challenge a highly-popular incumbent, which puts him far behind in a 2013 race.  Booker can build an organization in 2013 to challenge for the Democratic nomination to replace Frank Lautenberg, who will almost certainly retire a second time and leave an open field.  No other Democrat would have the standing in New Jersey as Booker does, and he may not even face a meaningful primary challenge at all.

That leaves Democrats empty-handed in next year’s election, though:

If Mr. Booker decides to forgo a run for governor, it would drastically shake up the race for Democrats, as party leaders across the state haven’t unified behind another candidate.

“If Booker doesn’t get in, it’s certainly a much more wide-open field,” said Ben Dworkin, director of the Rebovich Institute for New Jersey Politics.

That’s one way of putting it.  Another way is that they won’t have a prayer of defeating Christie.  The best they can do might be to run a promising young candidate who can get his feet wet in state-wide politics to run against him as a sacrificial lamb in order to raise his profile for future elections.