First Read: “Congress is about to get more polarized in the Senate with all the retirements of moderates and look at the House, a place most would think couldn’t get MORE ideologically divided. Just in the last month, on the Republican side, there have been the retirements of Virginia’s Frank Wolf, Iowa’s Tom Latham, and Pennsylvania’s Jim Gerlach. On the Democratic side, out are North Carolina’s Mike McIntyre (announced yesterday) and Utah’s Jim Matheson. If you toss in Arkansas’ Tim Griffin and New Jersey’s Jon Runyan, and the pool of congressional members willing to vote with the other side is shrinking. Whatever’s left of the middle or the pragmatic caucus is disappearing. And there wasn’t much of a middle to begin with. Every one of these retiring members is going to be replaced by someone more partisan. It doesn’t matter which party wins control overall, the two parties, ideologically, will be farther apart and that guarantees even more gridlock.”

Gov. Chris Christie (R) “is learning that being a Party of One can be pretty lonely when times get tough,” Politico reports.

“Democrats predictably condemned the New Jersey governor after a bombshell report Wednesday tied one of his top staffers to a burgeoning scandal that’s already been dubbed ‘Bridge-gate.’ More notable was the dearth of Republicans who rose to Christie’s defense — and, privately, the schadenfreude expressed by some of them that a man who’s never been shy about taking shots at others was suddenly on the receiving end.”

New York Times: “The usually verbose and swaggering Mr. Christie, who once mocked questions from reporters about the abrupt closing of lanes to the bridge, seemed at a loss for how to respond on Wednesday.”

“Prominent Republicans are working to recast the party’s message about tackling poverty and boosting the middle class amid concerns that a relentless focus on the troubles of Obamacare will not be enough to guarantee electoral success,” the Los Angeles Times reports.

“The move seeks to address widespread public anxiety about the uneven economic recovery, a topic that Democrats have largely had to themselves in recent months. But even as party strategists push for a higher-profile approach, conservative lawmakers face a difficult challenge in crafting a message that appeals to middle-income and working-class voters while maintaining support among the party base.”

“It’s the latest acknowledgment that Republicans’ traditional emphasis on fiscal austerity and smaller government — while popular among grass-roots conservatives and gospel to much of their House majority — has been difficult to sell among the broader electorate.”

Roll Call: “Two longtime House Democrats — Reps. Mike McIntyre of North Carolina and Carolyn McCarthy of New York — will not seek re-election in 2014, according to a Democratic aides.”

Jonathan Chait: “To this point, Chris Christie has treated the George Washington Bridge closure story as a joke, and national reporters have regarded it as a minor irritation. The public release of e-mails among his staff changes all that. The e-mails prove that Christie’s loyalists closed the bridge deliberately as political retribution, not as a ‘traffic study’ as claimed. They display an almost comical venality bordering on outright sociopathy. And they will probably destroy Christie’s chances in 2016.”

Chris Cillizza: “Molehills can grow into mountains in politics. This is now a serious problem for Christie.”

The U.S. Chamber of Commerce will step up its election-year efforts to challenge Tea Party candidates in Republican primaries and back candidates who favor trade, energy development and immigration reform, Bloomberg reports.