Let’s face it, the “Rudy wins NJ” line is just crap.
Try more like 15-20 years ago. The demographics have changed drastically. There has been a large outflow of Republican leaning voters, especially from Bergen, Middlesex, and even Monmouth Counties, to say nothing of inner suburban areas like Clifton in Passaic County. In their place has come a large wave of immigrants from Asia (India and Korea especially) and Latin America, to say nothing of ex-New Yorkers. The latter group are the main reason that the Dems now controls such once solidly Pubbie towns as Summit, Millburn, and Tenafly.
It has NOTHING to do with the national party, it has to do with corruption and the collapse of the local party and shifting demographics. The GOP has run moderate candidates such as Forrester and Kean in recent years, and they have lost to the likes of Lautenberg and Menendez. Forrester and Kean would have probably won had so many Republican voters moved to North Carolina, Florida, and Pennsylvania.