update: Welcome DeLongians. Now that he has sent you here I am going to do a little bate and switch and write more on what's wrong with people discussing issues with similar people. I have some sense of shame so the added text is at the end of the post.
John F. Harris and Jim VandeHei have a very good Nostra Colpa* on what is wrong with the campaign press. Mainly, they say they agree with everything that bloggers like Atrios have been writing about them and their colleagues. They don't have a very practical proposal for the way forward. Jonathan Chait once had a good idea, roughly "get on your duffs." In 2004, Chait wrote that he wasn't going to the Democratic convention which was the experience most like junior high he has had since junior high (key questions -- where are the good parties and how can I get invited). He said he could get all the information he needed from his office (or hell his house) in Washington, since it is on the web.
This would help Harris, VandeHei et al deal with their big problem II
2. The echo chamber
Check out the nicer restaurants in Manchester, N.H., or Des Moines, Iowa, in the political season and you will see the same group of journalists and pols dining together almost every night. We go to events together, make travel plans together and read each other's work compulsively. We go to the same websites — the Drudge Report, Real Clear Politics, Time’s “The Page” — to see what each other is writing, and it’s only human nature to respond to it.
That is one chief reason the “Hillary is inevitable” and “Hillary is toast” narratives developed so quickly and spread so rapidly.
How about just not going there. I don't mean not going to the nicer restaurants, I mean not going to Iowa and New Hampshire. If all they had to go on was politicians' speeches, press releases and web pages, their coverage would be more focused on the issues, more original and more valuable. The old fashioned idea that you have to be physically present to know what is going on helps trap reporters in the echo chamber.
It would also help with this other problem "reporters leave their homes, spouses and families for long stretches to cram into crummy hotels and smelly buses to cover campaigns."
Now there are two catch phrases about crowds "the wisdom of crowds" and "the madness of crowds." I prefer the second and not only because it is due to Isaac Newton. The first is talking about averages not crowds. It is a fact that if you ask many people for a forecast (or estimate or guess) of a number, the average forecasts (or ...) is , on average, much closer to the truth than most of the individual forecasts (in my experience better than the vast vast majority).
However, this occurs when the different forecasts (or estimates or etc) are made more or less independently then averaged. It is not the same if the participants are brought together and discuss till they reach a consensus. If you take a bunch of people and ask them about something then break them into groups and have them discuss it in their little groups, the opiinions in the little groups moves farther from the overall average and usually farther from the truth (See collected works of Thaler).
This is a direct contradiction of one of the core principles of liberalism which holds that debate and discussion are good for the quest for truth. A mechanical average works better.
This is unpleasant, but the fact that the best way to do their job is to do whatever else in life they enjoy and just stop obsessing on it should be welcome.
My advice -- get a life
(needless to say I haven't followed my own advice).
quick update: I wrote this just before reading this excoriating Maureen Dowd for reporting on New Hampshire while she was in Jerusalem. Sargent does have a point, of course, the column is datelined New Hampshire which is misleading (but allowed according the NYT rules since Dowd had been in New Hampshire). It included reporting by an assistant whose name appears nowhere. Unfair but I don't care. The reporting is on statements by ordinary people not campaign flaks, so it is not at all what I was talking about above.
*that's Italian. I don't read or write Latin.
update II: The problem of people with similar backgrounds discussing the issues is more serious than a few bad predictions. It can lead the opinion of each person in the group towards views that have some appeal to everyone in the group. This can have terrible results if the group consists only of people with the same self interest. A rich person would have to be selfish to decide his views on tax policy based only on self interest. A group of rich people discussing the matter will find that the consensus puts high weight on the view that reduced taxation of rich people have excellent incentive effects. This can happen just because everyone winces if someone proposes raising taxes on rich people. Unfortunately Washington insiders are, on average, rich.
The same group think that lead reporters to think that "everyone who knows anything agrees that Clinton is toast" can lead Washington insiders to think that "class war is bad" or "Social Security is an immensely expensive program which doesn't do anything significant for anyone who matters". Class interest can be much more influential than individual interest if people discuss matters exclusively with other members of their class.