All of the news coverage about the fall of Ted Haggard is once again highlighting the fact that the media is unfamiliar with evangelical culture -- and lingo. One of the most glaring mistakes they make is confusing the words evangelical and evangelist. (UPDATE: USA Today corrected the headline which referred to Haggard as an evangelist in the linked story.)
An evangelist is someone who proclaims the "evangel" (good news) with the intention of calling people to conversion. In the broadest sense all preachers are evangelists because they proclaim good news. But in the more common sense an evangelist is someone who specializes in preaching to, or "winning", unconverted people. Billy Graham is an evangelists in that sense.
An evangelical is someone who identifies with evangelical emphases. Traditionally the emphases which define evangelicalism are: the authority of the Bible, the necessity of personal faith in Christ Jesus, and a globally focused mission-mindedness. While evangelicals are passionate about challenging people to turn to Christ, not all evangelicals are necessarily evangelists.
Evangelicalism is actually a broad set of movements. In the US you can find evangelicals in all of the mainline churches. There are, as well, some denominations which are defined by their evangelical emphases. And then within the last 30 years there has been a proliferation of independent evangelical churches, such as that which Haggard started in Colorado Springs.
Ted Haggard was also the president of the National Association of Evangelicals, a blanket organization which represents many evangelicals and evangelical churches.
As far as I know he is an evangelical but he isn't known as an evangelist.