Polls with this many undecideds are worthless.
But it is interesting that despite a 61% approval rating he's stuck at 41-42%. Even if Sununu wins re-election, it's very possible he could be like Hassan in 2014, who was super popular and was expected to cruise to re-election, but the political environment got a some dude relatively close.
Scott Brown's not a some dude, though an established New Hampshire GOP pol who wasn't obviously carpetbagging would've won that race.
Scott Brown ran against Shaheen, not Hassan...