PRINCETON, NJ -- The latest Gallup Poll Daily tracking report from Wednesday through Friday, including two days of interviewing after Wednesday night's final presidential debate, shows Barack Obama with a 50%to 42% lead over John McCain among registered voters.

Obama's eight-point lead among registered voters is similar to his margin among this group over the last several days. Gallup's likely voter scenarios show a closer race. Gallup's expanded likely voter model, based on respondents' answers to questions about current interest in the election and intention to vote, shows a 50% to 46% race, which is a more narrow lead for Obama among this group than in previous days. If turnout in this year's election follows traditional patterns by which the voting electorate skews towards those who usually vote as well as those who are interested in this year's election, the race shows Obama leading at 49% to 47%, where it has been among this group for three days. (To view the complete trend since March 7, 2008, click here.)

-- Frank Newport

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

Survey Methods

For the Gallup Poll Daily tracking survey, Gallup is interviewing no fewer than 1,000 U.S. adults nationwide each day during 2008.

The general-election results are based on combined data from Oct. 15-17, 2008. For results based on this sample of 2,796 registered voters, the maximum margin of sampling error is ±2 percentage points.

For results based on the sample of 2,572 "traditional" likely voters (based on the model taking into account current voting intention and past voting behavior), the maximum margin of sampling error is ±2 percentage points.

For results based on the sample of 2,263 more broadly defined likely voters (based on the model taking into account current voting intention only), the maximum margin of sampling error is ±2 percentage points.

Interviews are conducted with respondents on landline telephones (for respondents with a landline telephone) and cellular phones (for respondents who are cell phone only).

In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls.