Mark Blumenthal | November 30, 2007
Today's new ARG poll of likely caucus goers in Iowa generally confirms the trend reported by other polls that we see in our Iowa chart. Barack Obama has been rising in recent weeks, while Hillary Clinton's support -- which had been trending upward since the summer -- has mostly leveled off.
Keep in mind that the regression based trend lines on our charts are more conservative by design. As Professor Franklin frequently reminds us, that characteristic helps us isolate real changes while filtering out the short term "noise" from differences in methodology or simple sampling error.
Another lower tech way to try to see trends amidst the noise of differing methods is to do what I call "apples- to-apples" averages of comparable polls. In this case, ARG, Rasmussen and Strategic Vision have all fielded surveys in the last week or so, as well as earlier in the month. Whatever qualms we have about their methodologies, their surveys are done the same way each time and are at least helpful in spotting trends. And while the change is relatively small, they are essentially consistent: All three show small increases for Obama. On average, the three surveys indicate a three point gain for Obama and a one-point drop for Clinton.
Has Barack Obama "moved ahead" of Hillary Clinton? Neither our chart, this "apples-to-apples" average nor any of the polls individually (if we consider sampling error), shows that yet, but the trend is clearly moving in his direction.