It's not just the CNN polls though. It's all the polls, including WSJ, Rasmussen and even Fox News.
A poll is not the collective will of the American people, and it is subject to interpretation and manipulation, based on how questions are worded, how many pinheads are off from work that day, how many airheads the pollster encounters, the mood of the pollster, and how reporters spin the results.
If we could just rely on the polls to tell us accurately what every American thinks, we would not need a Congress or a President. We could simply have a big computer in D.C. to tabulate the daily poll results from across America, and govern according to that. There is a valid reason we don't do that! Polls are NOT ALWAYS RIGHT! The ONLY poll that EVER matters, is the one held on Election Day at your local precinct. Aside from that poll, the only other possible polls that matter, are the ones taken on the floor of Congress when legislation is presented for vote. ...Like the numerous votes taken to withdraw from Iraq, which have all failed resoundingly.