There is Gary Johnson, for the Libertarian Party and Jill Stein for the Green Party. Polls show that Stein receives about 1% of the vote. I think this reduces the Democratic polls. Johnson has polled as much as 14%- that’s a lot. Libertarians I feel are closer to Republicans than Democrats, but it very much depends on the issues. One thing is clear, and they want much less government spending. So, that makes them seemingly like Republicans. But, they may also be very against bail out of Wall Street- and more aligned with Bernie Sanders.
As Republicans and Democrats escalate their campaigns, I suspect the third party candidates will be drowned out, and Johnson will be lucky to get 1- 3%. But for the toss-up states, this could be significant and hard to factor in to the polling data.