All of us following the U.S. presidential election campaign have the feeling, I’m sure, to be drowning in opinion polls. Every day, there are new polls, both nationally and state by state, and especially in the ten or so “battle ground states,” where the election will be decided.

And if you have followed my blog about America, you’ve probably also noticed that I keep close tabs on what Nate Silver writes on his political statistics blog in the New York Times called FiveThirtyEight — an excellent source of information during an election campaign where so much is about the polls and dthe importance of how these new, daily measurements are interpreted.

Last night, I went to listen to Professor Simon Jackman, political scientist and political statistician at Stanford University, who was in town to give a lecture.

“Obama wins in a squeaker,” predicted Jackman, but the situation is extremely even — “a game of inches:” 47 percent for Obama, 47 percent for Romney. According to Jackman’s model, Obama leads today with 267 electoral votes to 206 for Romney (270 needed to win). Five states with a total of 65 electoral votes are “toss ups”: Colorado, Florida, New Hampshire, Virginia and Wisconsin, while Iowa, Nevada, Ohio, and Pennsylvania lean to Obama, and North Carolina to Romney.

This is not a forecast but a compilation of the 517 polls —  “poll averaging” — which Jackman describes in this interesting article in the Huffington Post. This method is necessary to really explore the political situation, and he warned of polls with only 800 or 1000 or 2000 respondents. They don’t tell the correct story.

Jackman also described in his lecture how it is becoming increasingly difficult to produce good and reliable polls. People don’t want participate. They don’t have time. Why should hey spend 15 to 30 minutes on the phone with someone they don’t know, and without getting paid? And he described the problem of reaching young voters, if the survey does not use cell phones and how the Internet is becoming increasingly important to the polls.

Jackman also spoke about political bias in the polling firms. None of them stand out as extra special, but they have their sympathies. Of the major polling firms, Pew is pro-Obama and Rasmussen pro-Romney. Gallup leans towards the Republicans, while the polls from Fox News, surprisingly to me at least, are close to the ideal political neutrality.

Still, Jackman writes, “it would be unreasonable to conclude that the polls are giving us a qualitatively incorrect impression of how the election is shaping up.”

Here is his article on the subject in the Huffington Post.