Weak Republicans = Independents

via Survey USA;

In all four of these districts, we observe significant movement away from the Republican incumbent and towards the Democratic challenger, with the Republican's lead decreasing by between 9 and 13 points. Furthermore, all four districts show a shift in the party distribution of likely voters, with the Republican-Democrat difference changing towards Democrats by between 4 and 11 points. Two possible explanations for this shift are:

1) Republicans are becoming less likely to vote, and Democrats are becoming more likely to vote;

2) Some "weak Republicans" are now identifying themselves as Independent, while some left-leaning Independents are now identifying themselves as Democrats.

It is unclear at this time which of these explanations is more significant, or how persistent the shift will be. But the consistency of the pattern suggests that the movement in these 4 contests may be driven by a nationwide trend affecting all House races, rather than by factors specific to the individual districts.

While this excerpt wasn't referring to the NY13 race specifically, it is not a far fetch to apply their findings. After all Rep. Vito Fossella started running away from his Republican party and declaring himself an Independent months ago.