Actually Congressional staffers read their home town newspapers most closely, which is one of the problems with the whole obsession with DC pundits. People in DC and NYC think the world revolves around their media, but home town papers and television stations matter far more. I believe studies consistently show that average folks watch their local news channels far more consistently than the national news.
And those home town papers, even in urban areas, are far more diverse on Israel than the New York newspapers (heavily overrepresented on Alterman's list), which while being "important" papers also reflect their heavily Jewish readership and are therefore not exactly the best metric.
The Boston Globe has always been more balanced on Palestinian issues (although I haven't checked since it was acquired by the NY Times) and the LA Times has regular writers like Robert Scheer who are very critical of Israel. Commondreams is not an original publishing source but republishes from newspapers and magazines around the country. If you check it out, you will find columns criticizing Israel in newspapers ranging from the LA Times to Philadelphia Inquirer along with smaller magazines like Tikkun etc. Justin notes an example from Chicago.
The DC-NY pundit folks think of themselves as far more important than they really are-- real media power, at least over any particular politician, lies with the media in their home town. This also goes to the problem with conservatives trashing the "liberal Media" while ignoring the large number of conservative newspapers in towns and cities across the country. Studies on media bias usually sample a few big city newspapers that like the NY Times or LA Times which should be liberal considering the populations they service; in fact, they are often far less liberal than the regions they serve. So Alterman is just joining hands with conservatives in finding the shocking fact that New York city newspapers serving heavily liberal Jewish populations tend to reflect a, surprise, liberal and Jewish outlook.
-- Nathan Newman