Do Brian McLaren and Mark Driscoll both have a legitimate claim to be an "evangelical?" Of course, I would make the distinction that an evangelical can be either liberal, moderate or conservative but that is neither here nor there.
I think Roger Olson's post moves us towards a possible consensus. Roger Olson stated, "It has always seemed self-evident to me that movements cannot have boundaries. In fact, secretly, only to myself, I have long considered people who think movements can have boundaries either disingenuous or sociologically ignorant. Organizations have boundaries; movements do not. It’s self-evident. Movements have centers, not boundaries" (1).
If one looks at fundamentalism within the 1920s to the 50s, you get a clear look into the heart of remnant theology rooted in dispensationalism, coupled with the fear of the Soviet empire in the 60s and so on. Today, you have many folks within Protestantism who would prefer a smaller venue with less distinctions in term of doctrinal strife.
Or, in other words, doctrine trumps fellowship.
So, it makes sense that many conservative Christians put inerrancy up as the deciding vote on whether or not one is an evangelical. Besides the difficulty in defining inerrancy to most people's satisfaction, one is really out in a leaky lifeboat if they think the resurrection is as important as the complete historical and scientific accuracy of Scripture.
Biblicism. Conversionism. Crucicentrism. Activism. Bebbington put these out there to attempt a calm in a sea of bewildering chaos. Beyond being disputed by DA Carson among others, people make a point that doctrine is the method by which we measure one's orthodoxy, not character or sociology.
I think we've got multiple deep-rooted problems here, not the least of which is that the people who want to define the legitimacy of certain trump card doctrines all more or less believe the same thing. Therefore, evangelicalism is an exclusive or even ecclesiocentric patchwork quilt, not a big billowing tent.
Another issue comes about when you have people who seem to fall outside the realm of "evangelical" but still desire the label. Do we honor the request for the title, redefine the title or entirely exclude the inquirer? I confess, I don't know.
Olson, "Thus, I argue that evangelicalism, like Pietism, charismatic movement, “New Age,” etc., etc. refers to a category that can only be defined in terms of prototypes that constitute a center. I would put Noll’s and Bebbington’s four hallmarks at that center and with them Jonathan Edwards and John Wesley. What did those men have in common that was not as noticeable among most of their peers in Protestant Christianity? I would say those would be biblicism, conversionism, crucicentrism and activism. And I would add to that a tendency strongly to defend the Great Tradition of Christian orthodoxy (broadly defined). Yes, to be sure, there were others who displayed the same characteristics, but they especially stand out as the prototypes of the Great Awakenings of the eighteenth century that gave birth to the modern evangelical movement" (1).
I will confess that I think evangelicalism is a big tent constituency, and I think one can very easily be an evangelical if they hold to the general terms outlined above. The issues these days is more or less a redefinition of the terms.
The question is, do we allow it or fight it? I have no idea.