PRINCETON, NJ -- The latest Gallup Poll Daily tracking report finds registered voters preferring Barack Obama (50%) to John McCain (43%) when asked who they would vote for if the presidential election were held today.

These results, based on Oct. 9-11 polling, represent a narrowing of Obama's lead over McCain. Obama led by double-digits for three consecutive days last week, but now his advantage is down to seven percentage points. Obama has led in each of the last three individual days' polling, but by less than double-digits each day, suggesting that the race is, in fact, tightening.

Obama has generally held an advantage over McCain since mid-September, when the imminent failure of several large financial institutions made the economy an even bigger concern than it had previously been. (To view the complete trend since March 7, 2008, click here.)

Likely Voter Estimates

Obama's current advantage is slightly less when estimating the preferences of likely voters, which Gallup will begin reporting on a regular basis between now and the election. Gallup is providing two likely voter estimates to take into account different turnout scenarios.

The first likely voter model is based on Gallup's traditional likely voter assumptions, which determine respondents' likelihood to vote based on how they answer questions about their current voting intention and past voting behavior. According to this model, Obama's advantage over McCain is 50% to 46% in Oct. 9-11 tracking data.

The second likely voter estimate is a variation on the traditional model, but is only based on respondents' current voting intention. This model would take into account increased voter registration this year and possibly higher turnout among groups that are traditionally less likely to vote, such as young adults and racial minorities (Gallup will continue to monitor and report on turnout indicators by subgroup between now and the election). According to this second likely voter model, Obama has a 51% to 45% lead over McCain. -- Jeff Jones

(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. 9-11, 2008. For results based on this sample of 2,783 registered voters, the maximum margin of sampling error is ±2 percentage points.

For results based on this sample of 2,134 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 this sample of 2,286 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.