All who are tempted to take early polls on Presidential preferences for ’08 seriously are directed to Mystery Pollster’s pre-vacation post “2008 Presidential Polling in 2005: A REALLY Big Grain of Salt.” Yes, Hillary and Guliani or McCain may look like front runners now. But that doesn’t mean squat, if historical experience is worth anything. Mystery Pollster analyses a study of early polls by The National Journal Hotline and concludes:

The polls for the 2004 Democratic primary provided “the best example of tainted primary polls.” Three candidates who did not run (Gore, Clinton & Bradley) dominated the early trial heats, while the ultimate “frontrunners” (Kerry, Edwards & Dean) barely registered:
WH ’04 Dem Primary Averages
41% Al Gore
19% Hilary Clinton
9% Joe Lieberman
8% Bill Bradley
7% Dick Gephardt
4% John Kerry
2% John Edwards
2% Bob Kerrey

Mystery Pollster notes similar results for other recent presidential polls and elections and adds:

…the horse race questions you are seeing on the 2008 race for the White House are sampling segments of the population that are three to four times larger than the electorates that will actually decide each nomination. And keep in mind, we do not conduct a national primary, but a series of statewide primaries.
…It may be helpful to consider that private campaign pollsters — the people hired by the presidential candidates — do not bother with this sort of national primary horserace poll. When they begin to do their internal surveys for presidential candidates, campaign pollsters will focus more on sampling individual states that come early in the process (Iowa, New Hampshire, South Carolina, etc) rather than looking at a national sample. And even then, they pay far less attention to horse-race questions at this stage in the race than to favorable ratings that tell us how well each potential candidate is known.

So leave early speculation about the presidential nominees of both parties to the time-wasters. Dems have enough to worry about in ’06 — to make the most of the opportunity to regain control of at least one house of congress. For more on the importance of meeting this challenge, see our July 25 post “Dems Should Focus More on Congressional Campaigns.”