His advantage could be as narrow as 7 points, depending on likely voters

PRINCETON, NJ — Voter preferences in the presidential race continue to be generally auspicious for Barack Obama’s election prospects only three weeks ahead of the eve of Election Day. Obama leads McCain by 10 percentage points, 51% to 41%, among all registered voters, according to Gallup Poll Daily tracking from Oct. 10-12.

The percentage of registered voters favoring Obama has been 50%, 51%, or 52% in each Gallup Poll Daily tracking report since Oct. 4. Support for McCain has been a steady 41% to 43% across the same time period. Thus, although the gap between the two candidates has varied from seven to 11 points in recent days, voter preferences have, in fact, been quite stable. (To view the complete trend since March 7, 2008, click here.)

Likely Voters

Among typical “likely voters” — the subset of registered voters who appear most likely to vote on Election Day according to their current voting intentions and past voting behavior — Obama’s lead is a slightly narrower seven points, 51% to 44%. This assumes that about 60% of the voting age population will vote, slightly higher than the 55% who turned out in 2004.

Among a more broadly defined likely voter group that only takes into account current voting intentions — not past voting behavior — Obama’s lead is the same 10 points as among all registered voters, 53% to 43%. This group represents approximately two-thirds of the general public, a significantly higher proportion than has turned out in any recent election. — Lydia Saad

(Click here to see how the race currently breaks down by demographic subgroup.)