By John Whitesides, Political Correspondent
NASHVILLE, Tennessee (Reuters) - Democratic presidential candidate Barack Obama has a slim 2-point lead on Republican rival John McCain in a tight White House race, according to a Reuters/C-SPAN/Zogby poll released on Wednesday.
Obama led McCain by 47 percent to 45 percent in the national poll, within the margin of error of 2.8 percentage points. Obama led by 3 points in Tuesday's poll.
Four percent of voters said they were still undecided.
The daily tracking poll, which will sample public opinion until the November 4 election, showed Obama leading among two crucial swing voting blocs. He has a 9-point advantage among independents and a 7-point edge among women.
"This race is at equilibrium," pollster John Zogby said, adding neither candidate has been able to take full advantage of voter unhappiness with the country's direction.