03/28/2008 02:45 am ET Updated May 25, 2011

Looming: The Final, Expectations-Setting Des Moines Register Poll

It is one of the worst kept political secrets in this town: the last Iowa Poll before Thursday's Iowa caucuses is expected to be online this evening, before it is published Tuesday in The Des Moines Register.

As the most closely watched and respected measure of public opinion in the state, the poll will likely have significant influence on the media storyline in the final days of campaigning in the first-in-the-nation-caucus state.

The paper traditionally runs a tracking graphic that shows how support measured each night (typically at least two or three) that the telephone bank was dialing for poll participants.

Any positive trend from night to night in that graphic will likely be seized on by the media as a sign of "momentum" or a "surge" heading into caucus night.

With a significant number of voters still believed to be undecided in both the Democratic and Republican contests, the poll could give those people help in making their decision, if they want to go with a "winner."

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