Obama and Biden now lead McCain and Sarah Palin 48 percent to 40 percent. This is the first CBS News poll to include the vice presidential candidates in the horserace question. The eight-point lead for the Democratic ticket is up from Obama's three-point lead before the convention. But there are still a significant number of voters who have yet to firmly make up their minds.
Before the Democratic convention, McCain enjoyed a 12-point advantage with independent voters, but now Obama leads among this group 43 percent to 37 percent.
Obama's lead among women has also grown to 14 points (50 percent to 36 percent), and the Democrat maintained the lead he had before the convention among voters who supported Senator Hillary Clinton in the Democratic primaries.
The poll shows an increase in the number of Obama voters who are enthusiastic about him. Sixty-seven percent of Obama voters say they enthusiastically support him, which is up from 48 percent who said so before the convention.
Sixty-three percent of registered voters say Obama understands their needs and problems, while just 41 percent say that about McCain. And after the Democratic convention, 58 percent of voters say Obama is tough enough, which is up from 48 percent in early August.
The CBS News started polling the evening after McCain named Sarah Palin as his running mate. Twenty-eight percent of voters now say the vice-presidential candidates will matter in how they vote, which is up from the 25 percent who said so before Biden and Palin were named to their respective tickets.
This poll was conducted among a random sample of 875 adults nationwide, including 781 registered voters, interviewed by telephone August 29-31. Phone numbers were dialed from RDD samples of both standard landlines and cell phones.