But the BBC's James Coomarasamy, in Washington, says that while Mr Obama has held a pretty steady lead for several weeks, there are a number of factors that could undermine the predictions of the pollsters. Among them, he says, are the role the Illinois senator's skin colour may play in voters.

But the BBC's James Coomarasamy, in Washington, says that while Mr Obama has held a pretty steady lead for several weeks, there are a number of factors that could undermine the predictions of the pollsters. Among them, he says, are the role the Illinois senator's skin colour may play in voters.

But the BBC's James Coomarasamy, in Washington, says that while Mr Obama has held a pretty steady lead for several weeks, there are a number of factors that could undermine the predictions of the pollsters. Among them, he says, are the role the Illinois senator's skin colour may play in voters.

But the BBC's James Coomarasamy, in Washington, says that while Mr Obama has held a pretty steady lead for several weeks, there are a number of factors that could undermine the predictions of the pollsters. Among them, he says, are the role the Illinois senator's skin colour may play in voters.

But the BBC's James Coomarasamy, in Washington, says that while Mr Obama has held a pretty steady lead for several weeks, there are a number of factors that could undermine the predictions of the pollsters. Among them, he says, are the role the Illinois senator's skin colour may play in voters.