Today's Update

via TPM today:

Obama Maintains Big Lead In Today's Tracking Polls
By Eric Kleefeld - September 30, 2008, 1:08PM

Here's a wrap-up of the four major national tracking polls for today -- the first day on which we've gotten three-day tracking polls that were taken entirely after Friday's debate. Barack Obama continues to hold a big lead:

• Gallup: Obama 49%, McCain 43%, with a ±2% margin of error, compared to a 50%-42% Obama lead yesterday.

• Rasmussen: Obama 51%, McCain 45%, with a ±2% margin of error, compared to a 50%-45% Obama lead yesterday.

• Hotline/Diageo: Obama 47%, McCain 41%, with a ±3.2% margin of error, compared to a 47%-42% Obama lead from yesterday.

• Research 2000: Obama 51%, McCain 41%, with a ±3% margin of error. Yesterday, Obama was up 51%-42%.

Adding these polls together and weighting them by sample sizes, Obama is ahead by a margin of 49.8%-43.1%, virtually the same as yesterday's 49.8%-43.1% lead.