A new swing state has come on to the radar courtesy of the Public Affairs Institute at Minnesota State University Moorhead, which has conducted a poll of 606 voters in North Dakota showing Barack Obama leading John McCain 45 per cent to 43 per cent. That might not be much to go on – the state was last surveyed a month ago by Rasmussen, who had McCain leading 53 per cent to 40 per cent – but it’s enough to put it in the Obama column for purposes of my own polling aggregate methodology. As explained in previous posts, this involves using all the polling going back to October 1 or as much of it as is necessary to produce a sample of over 3000, with each poll weighted according to its sample and adjusted according to the shift in the Real Clear Politics national poll average since the day it was conducted. Note that McCain remains curiously competitive in Ohio.