This is the standard ‘big tent’ definition of Evangelicalism, using my words:

Evangelicalism is a Christian Protestant movement that began in the 1730s in England and America, led by the likes of Puritanism, Pietism, and Methodism in England, and the likes of Jonathan Edwards and George Whitefield in America. It maintains four essential priorities:

• the primacy of Scripture

• the centrality of Christ’s death as substitutionary atonement for human sins

• the necessity of personal conversion

• the importance of ‘kingdom living’ (actively following Jesus by engaging such efforts as the spiritual devotions, Christian community, deeds of compassion, justice, etc)

Anything else, or anything less, is not Evangelicalism-proper, but someone’s personality or opinions fused in with these four pillars. For instance, Evangelicals did not vote George Bush into office. Political/social conservatives, who also happen to be Evangelicals, voted him in. Further, many political/social liberals, who also happen to be Evangelicals, voted Barrack Obama into office this time around.

As another example, A Christian who says she is an Evangelical because she really has a heart to love the poor is not an Evangelical. She is a Christian who has a passion for a Christian principle which also happens to be one-quarter of the essential priorities of Evangelicalism.