The Forum has just published a New poll of North Dakota: Obama 45, McCain 43, Undecided 12. The poll of 606 voters has a margin of error of 4%, so we cannot definitively say Obama is ahead, but this is great news.
For comparison, 538's summary of polls shows that in the three September polls McCain lead by 13, 9, and 14 points. However, way back in July, his lead in two polls was only 1 and 3 points, so it's plausible the state has swung back.
This poll was conducted by the Public Affairs Institute at Minnesota State University Moorhead.
(ht: sphexus of Open Left)