I think this is bad for Romney. If he only wins NH by 10 points people are going to wonder why he didn't win by more.
Are you talking about the primary or the general. This poll has him up by 30 in the primary and thus its hard to say this is bad sign unless you think the poll is wrong in which case your phrasing makes no sense because then it couldn't be a bad sign because the sign itself is wrong.
If you are talking the general election, if Romney is winning by 10 in NH, Obama is so unbeleivably screwed nationwide.