Now that I have thought about Dr. Jackson's characterization of evangelicalism a bit more, it has occurred to me that attempting to include a "spiritual ethos" in a description of evangelicalism is to fall prey to a "sociological" interpretation of evangelicalism. Is it possible to be robustly "evangelical" without having the "spiritual ethos" of the Wesleys and their descendants?
I think so.
Perhaps contemporaries should focus on the theological distinctives of the evangelical movement in order to determine our identity in such a way that does not preclude other types of "spiritual ethos." I am envisioning something like the Catholic Church, who has a robust body of doctrine that permits various spiritualities to all be present within it. If evangelical theology is Trinitarian, then it is distinctly pneumatic. The emphasis on the Holy Spirit begins in Calvin, is developed and preached by Wesley and Edwards, and continues until today. However, there is no need to require an "ethos" of "conversion or renewal" that many theological evangelicals may not have, but rather a robust theology of the Spirit and the Christian life to be thoroughly (and historically!) evangelical. In other words, to be an evangelical does not mean having certain experiences of the Spirit, but rather to affirm certain doctrines about Him and His working.
This does not mean that other theological commitments should be divorced from the evangelical identity. Jackson is right to locate evangelicalism within the Reformation heritage. What it does mean, though, is theology should determine identity, and theology alone. Sola fide, sola scriptura, and what I have outlined above may suffice as the "demarcating lines" of evangelicalism.