The latest Pew survey, a detailed study of the both Democratic and Republican races, finds that "the likely outcome of these contests is more in doubt than in any election cycle in recent history."
It's close. In the Democratic contest, for example, the outcome "may well hinge on a generation gap that has gotten much less attention thus far than has the gender gap."
December polls by ABC/ Washington Post and Newsweek showed Barack Obama not only catching up with Hillary Clinton, but pulling slightly ahead among likely caucus goers. But the internals of the polls suggest that Obama's lead is indeed a fragile one. In the Newsweek poll, the Illinois senator tops his New York rival by a wide margin among voters who will "probably" vote (40% to 27%), but among those who say that they will "definitely vote" the race is even (31% vs. 32%).
This gap reflects a pattern apparent in both December polls. Obama runs far better among younger voters, who turn out less reliably than older voters. In the Newsweek poll Obama has a 25-percentage point lead among those less than 50 years of age, while Hillary leads by 15 points among those ages 50 and older -- a spread wider than the gender gap recorded in Iowa.
For Obama and Clinton -- as well as for John Edwards, who is in striking distance of the front runners in most polls -- preferences and enthusiasm for the candidates are not particularly linked to judgments about which candidate comes closer to the voter's position on the issues. The pluses and minuses are personal attributes: Hillary's experience, electability, and image as a strong leader appeal to her older and somewhat more conservative supporters. Obama's likeability, compassion and potential to effect change are his strong points with his younger, somewhat more liberal backers in Iowa.
The Democratic race in Iowa is likely to hinge on how well the campaigns can motivate their potential backers to turn out for the complicated and time-consuming caucuses.
More on the campaigns -- and the Republican contest -- the Pew report is here.
