Looks like Cory Booker has made up his mind, NBC New York reports:

Newark Mayor Cory Booker will not challenge New Jersey Gov. Chris Christie in next year’s gubernatorial race and will instead run for U.S. Senate in 2014, political sources familiar with his decision tell NBC 4 New York.

Booker will seek the U.S. Senate seat held by fellow Democrat Frank Lautenberg when his term is up in 2014, political sources tell NBC 4 New York. Lautenberg, 88, is the oldest current senator. He first served in the U.S. Senate from 1982 to 2001 and has served since his re-election in 2003. … Booker is expected to tweet his decision to his more than 1 million followers some time Thursday.

[Update 11:20 a.m.: It’s official. “As for my political future, I will explore the possibility of running for The United States Senate in 2014,” Booker writes in a Star-Ledger op-ed that just went live.]

Booker appeared to have two obvious choices when it came to his political future: He could challenge Christie next year or wait until 2014 to make a run at the Garden State Senate seat currently held Lautenberg. Looks like he’s choosing the latter.

Political observers in Newark and Washington had long been dreaming of a Booker-Christie matchup next fall. But the prospects of that high-profile battle dimmed, and then ultimately disappeared, in large part thanks to Christie’s astronomically high approval ratings in the wake of Hurricane Sandy. A recent poll of New Jersey Democrats, meanwhile, showed a relatively easy path to the Senate for Booker by way of a primary challenge to Lautenberg, who would be 90 in 2014.