"The evangelical crackup" is the title of a lengthy story in the New York Times Magazine. The title is a bit more provocative than the actual article which does note some interesting happenings in the evangelical political universe.
I don't see an evangelical crackup because there's not a monolithic evangelical entity out there, in politics or elsewhere. Evangelicalism is more of a movement than an institution and that's true regarding political/public square engagement as much as evangelism.
I think there are some interesting developments in evangelical circles. The most promising one is the broader cultural engagement by evangelicals. An exclusive focus on politics by evangelicals is a mistake in my estimation and would mirror the error of the Left which views politics as the answer to society's problems. I applaud broader, personal social engagement because that's what Christians should be doing. Government by it's nature is ill-equipped to address the pressing social problems of the day. (This is borne out by the fact that the percent of people living in poverty hasn't improved since Johnson's "War on Poverty" began in the early 1960s. I think one could make the case that it has in some respects made matters worse, e.g. usurped the role of private charities and persons and created programs which encouraged people to develop bad patterns of behavior such as out of wedlock births, and the like.) That's why it's absolutely critical that evangelicals are personally involved in addressing poverty, AIDS, and other social problems.
I think the media tries to find the spokesman for evangelicals e.g. Dobson, Falwell, Robertson and it just doesn't work because of its diffused nature. I think the influence the media places on power or influence of particular evangelical leaders is generally overstated. Those viewed as leaders may voice the concerns of large numbers of evangelicals but they don't dictate what people will do.
I don't see evangelicalism as diminishing in influence with the passing of some of the prominent evangelical leaders like Jerry Falwell and D. James Kennedy. I think evangelicals have moved from a protest movement, e.g. Falwell and the Moral Majority in the 70s and 80s to a movement where individuals are personally engaged in the process by running for office, serving on staffs, being law clerks and judges. I think this is true not just for the public square but other areas as well.
I do think the war has changed the political calculus across the board, at least for a few years. (Though that could change if the situation changes for the better in Iraq.) It's drawn out the pacifist thinking of some and disillusioned others but I don't think it's changes the fundamentals of political involvement. I saw a poll recently which showed younger evangelicals are less likely to identify as Republicans but not less likely to identify themselves as conservative and are more pro-life than older evangelicals.
The media which deals in sound bites vainly tries to fit evangelicals into a neat little box. It generally doesn't work, because they're dealing with a movement not a monolithic institution.