On September 10, a CNN/ORC poll for the presidential race was released. See the results here. Scroll down to question 4, to find results for all candidates for registered voters, and for likely voters.
The registered voters show: Obama 50%, Romney 41%, Gary Johnson 4%, Jill Stein 2%, undecided/other 1%. This only adds up to 98%, so chances are the percentages for several candidates were on the verge of being rounded up.
The likely voters show: Obama 51%, Romney 43%, Johnson 3%, Stein 1%, undecided/other 2%.