I am not sure whether all polls should be taken at face value. I've been quite suspicious ever since I saw the ridiculous PPP national poll -
Romney 23, Santorum 38, Gingrich 17, Paul 13 - from 2/11. It was not even close to the 2 other major national polls. Fox News from 2/10 has
Romney 33, Santorum 23, Gingrich 22, Paul 15 , while Gallup Tracking has been in the field every day and on 2/12 is showing
Romney 34, Santorum 27, Gingrich 16, Paul 8 .
PPP has been a fairly accurate pollster on the state level, but they are affiliated with the Dems. It's in their interest to promote non-credible republican candidates. To show such a humongous jump immediately after Santorum 3-state sweep, when other pollsters are only showing a strong movement, but Romney still with a modest lead, is very suspicious. It also helped Santorum point to it and say - there - I am in the lead - I am the only alternative to Romney - give me money. It couldn't have been a better present to Santorum campaign.
I've noticed similar stuff with Rasmussen being more favorable to Santorum, while other pollsters were not reflecting it. Rasmussen is being awfully chummy with people like Hannity, who have been trying to indirectly prop up the anti-Romney's.
PPP's national poll is a glaring abnormality that should be called out. A difference of 20%+ from other reputable pollsters should be explained.