David Stahl, the mayor of East Brunswick (a suburban Democratic town of 46,000 in the suburban-and-urban Democratic county of Middlesex) has switched parties from Democrat to Republican. Stahl will seek election to the heavily Democratic 18th Senate district, currently held by gubernatorial candidate Barbara Buono.
In 2009, Christie carried Middlesex county in something of an upset, though arguably, given trends elsewhere in the state, you could say a statewide Republican now needs blue collar Middlesex to win. Republican candidates did surprisingly well here in 2009: Assemblyman Diegnan (D) won by a relatively narrow 26,317 to 24,091 margin against nobody Joe Sinagra (R). It's the most Republican of the Middlesex Senate districts (read: most suburban), and is theoretically winnable in a Christie-dominated GOP wave election.
It wasn't close in 2007 or 2011, but it is worth noting that Republicans picked up this seat in the 1991 anti-Florio superwave, with the incumbent winning upset re-election campaigns in 1993 and 1997.
If Christie does win huge, it won't be because voters like him as a Republican, it will be because he goes out of his way to not be like other Republicans. This would mean that he would have pretty limited coat tails.
