Even out of context truthful mudslinging is still mudslinging.
I think the cutoff date for polls for CNN is the 13th, so, there's a few more days worth of polls left. I don't expect Trumps poll numbers to suddenly collapse and even if he drops like 10%, he'd still be pretty much on top.
Also, Fiorina has been dropping like a rock nationally, though still seems to be doing well in NH.
If by "well" you mean 8th place.
She's doing better there (~5%) than her national numbers (~1%) but either way she's toast. She had her moment in the spotlight, started making shit up on par with Ben Carson, and then quickly faded into the background. At this point, it's becoming a bifurcated race. You have Trump and then you have a race to be the "anti-Trump" that will survive long enough for the establishment to rally behind. Right now, that's between Cruz, Carson and Rubio.
Cruz, I think, is trying to thread the needle and somehow be the alternative to Trump, but simultaneously not piss off the Trumpkins, so that he can win both camps. I think that's going to backfire spectacularly on him. He's going to come off as "Trump Lite", too extreme for the establishment, too establishment for the Trumpkins.
Carson has a serious image and credibility problem now. I think he keeps sinking.
Rubio seems the most likely to stay afloat and seem un-Trumpish enough to be a rallying point. He won't win over the Trumpkins in a million years (he's just another immigrant to them), but he might not need them if the rest of the party coalesces around him. The GOP's biggest dilemma is getting that cohesion. If they continue to pull apart into separate camps and candidates don't start dropping out fast, they'll dilute the anti-Trump vote in the primary states and Trump will get enough momentum going that he'll be seen as unbeatable. I think that at this point, barring a bunch of the other folks dropping out and lining up behind a single candidate, Trump takes Iowa, New Hampshire, Nevada and South Carolina. After that, there should be enough casualties in the field to start giving a sizable block of support to a counterweight option.
For the Democrats....I think Clinton will win Iowa, Sanders will win NH, and then Clinton will win everything else. Sanders *might* eke out a win in Colorado and among the expat votes (if he survives until early March), but that's purely a guess -- no polling out there for those races. He's doing better in the upper Midwest blue states like Minnesota, Michigan and Wisconsin, but still lagging Clinton by 10-20 points. He's dead on arrival in the South, which I just don't get.