NJ is a very pro-democrat state. Barack Obama won by 18% while only winning the nation by 3.9%. This puts NJ as 14% more favorable to Democrats than the nation as a whole. However, If Christie is the Republican nominee NJ polls about the same as the rest of the nation. Clinton leads Governor Christie by an average of 9.7% in nationwide polling. That means Christie is doing about 2% better against Clinton in NJ than he is doing in the nation as a whole. This suggests that Christie is getting a 16 point home state bounce when compared to 2012 when Mitt Romney did 14% worse than he did in the nation as a whole. In the 2008 election John Mccaine(R) did about 12% worse in NJ than the nation as a whole. In accordance with these results it also suggests if the race is tight nation-wide it will be tight in NJ, thus making NJ a swing state.
Quinnipiac found the other leading Republicans trailing Hillary Clinton between 20 to 23 percent.
How much better(+) or worse(-) Republicans
did in ntation as a whole vs. NJ
NJ Nationwide +/-
2000 Bush vs Gore -19 -.5 -18.5
2004 Bush vs Kerry -5.5 +2.4 -7.9
2008 Mccaine vs Obama -19 -7.3 -11.7
2012 Romney vs Obama -18 -3.9 -14.1
Christie vs Clinton -8 -9.7 +1.7
This poll shows that if Christie runs NJ would be a swing state. Republicans need to find states they can win in an election where the popular vote is very close. Hillary Clinton looks very strong in Florida and that looks a state that she would win even if the election were very close. One of the paths Christie would take would be to win NJ ,and PA, Colorado, Iowa, Ohio and every state Romney won.
If the election were held today Hillary Clinton would win in a landslide but if the popular vote were very close, the polling suggests Christie could win those above mentioned states as they have shown Christie polling better than he has in the nation as a whole.