Gallup

With Zogby and Rasmussen both showing Barack with a five point lead, Gallup jumps to 10% today.
Barack Obama leads John McCain in Gallup Poll Daily tracking interviewing conducted Wednesday through Friday by an identical 52% to 42% margin among both traditional likely voters and expanded likely voters. Obama leads by a similar 52% to 41% margin among all registered voters.

What happened?
Gallup's interviewing conducted Wednesday through Friday shows that 27% of registered voters who plan to vote have already voted. The trend in early voting has trended consistently upward on a day to day basis, moving from 7% of registered voters, who had already voted during the period of Oct. 17-19, to the current estimate of 27%. Another 8% of registered voters still indicate that they plan on voting before Election Day itself. The vote choices of these early voters -- all of whom are included in the likely voter pool since they are definite voters -- skew more toward Barack Obama than the sample average. Thus, more and more of these Obama-oriented voters' choices are being "locked in" to the likely voter pool through early voting, benefiting Obama. (To view the complete trend since March 7, 2008, click here.) -- Frank Newport