And when he does, I listen. Here's the full text of a very instructive memo that Greenberg sent around today, with the title "Race stable on final weekend: Review of public and overnight polls":

To give some perspective on the race in its final weekend, we might recall what Wolf Blitzer said on the day before the election, 2000: "And now, let's take a look at the latest poll numbers. The new CNN/USA Gallup Tracking Poll results are being released at this hour. It shows George W. Bush with 48 percent, Al Gore 43 percent, Ralph Nader with 4 percent, Pat Buchanan with 1 percent. And those numbers are similar to other tracking polls," going on to cite the Bush lead in polls for ABC, Washington Post, NBC-Wall Street Journal, CBS and MSNBC-Reuters- Zogby.

In fact, the public polls in 2004 show a remarkably stable and dead-locked race, with Bush stuck somewhere between 47 and 48 percent, short of what an incumbent should have to secure re- election.

The Democracy Corps has a new poll, conducted Friday night and Saturday morning. While the full survey will be completed on Sunday, the half-sample of 500 interviews conducted after the release of the Bin Laden tape, show the race unchanged compared to a survey completed Thursday night. The partial survey shows Kerry at 48 percent and Bush at 47 percent. Like the survey conducted before, it shows the two parties with equal numbers of party identifiers.

The Saturday respondents (250 interviews) were asked the following question: "I'm going to read you a pair of statements about the release of Bin Laden's videotape. Please tell me which one comes closer to your view.

-- It makes me think that George Bush took his eye off the ball in Afghanistan and diverted resources to Iraq.

-- It underscores the importance of George Bush's approach to the war on terrorism.

By 10 points (46 to 36 percent), voters were more likely to think that Bush took his eye off the ball. (These results will be updated when the full survey is completed on Sunday.)

The stability in this poll reflects the overall stability of the race for president. This past week, George Bush polled 47.9 percent as the average of the public polls. That represents only a .5 point change compared to the prior week. Indeed, if one looks at the polls released Saturday and including polling after the release of the Bin Laden tape, Bush’s vote stands at 48 percent in one (Newsweek), 47 percent in one (Fox), and 46 percent in two (Zogby/Reuters and TIPP). That is a weaker result than for the polls released earlier in the week and prior to last weekend.

(These results are based on the results for registered, when available, as that is consistent across polls and has been a better predictor of the final outcome.)

Kerry’s vote was also stable at 46.4 percent on average, up .1 percent compared to the previous week. That is a dead-even race, where the undecided will play the final role, as they almost always break heavily against the incumbent.

The undecided in the race is also stable. During this week, the average of the public polls was 4.4 percent. The polls completed for Saturday have an average undecided of 6 points. There is no evidence of undecided narrowing on this weekend or as result of recent events.

The Democracy Corps combined polls as of Friday showed that the undecided (prior to being pushed to a preference) leaned toward the Democrats by two-to-one and favored a significant change in direction over continuing Bush’s direction by 58 to 29 percent, also two-to-one.

The tracking for the Kerry campaign, conducted for the whole battleground and in key battleground states at the end of the week, including Friday night, show Kerry with a clear and stable lead.

Bottom line, amidst the intensity of campaign’s final days, it is important to keep one’s eye on the stability and structure of this race, with Bush still short of what he needs to win.