To take three Twentieth Century conversions of note, let's start with C.S. Lewis. Lewis was an angry young atheist running away from religion, who found that everything he really wanted was only found in the things he was running away from. Even after his dramatic turnaround and his life of championing Christian doctrine and values, he found it rather unnerving to be a Christian, at least a 20th Century one. He said that he found himself living as a converted pagan among apostate Puritans. He didn't just "join the other side." His following of Christ greatly influenced those who had never left the faith and made them see everything differently.
Another dramatic conversion, usually thought of as a political one, but at bottom also a deeply religious one, was that of Whittaker Chambers. Chambers was the real-deal Communist spy back in the 1930s. He eventually broke with his Soviet masters and began a spiritual journey that resulted in his becoming a Quaker. He tried to live a normal life, but got dragged into the mess surrounding Alger Hiss and other government-employed Communists. In the end, he found himself testifying in court and in print about terrible realities to which he was privy to a world largely in denial about those realities. He is mostly forgotten today, except as an object of scorn to those on the left, but everything he said in his testimony has been borne out in the end, and his view of the Cold War as primarily a spiritual struggle has been validated by many others, including Aleksander Solzhenitsyn.
And then we come to Chuck Colson himself, who not only repented of his own sin, but came to identify with all those in prison or connected with those who are. Colson saw prisoners as neither criminals nor causes, but as persons. He showed how one can, in fact, hate the sin while loving the sinner. His guilty plea allowed him to confront the corruption of the Nixon White House but also to testify against corruption in other administrations. He didn't excuse his own "side" while condemning the other "side," which is what most discussions of political corruption amount to. Like all the great converts, he challenged as much as he comforted. He took us to a place we could not have predicted, but which was inevitably closer to God.
There have been great leaders of the Church who have grown up entirely within the Faith. They have their own stories of spiritual stress and transformation. Luther and Wesley are good examples of that kind of conversion. But it is the ability of God to turn enemies into exponents, to make outsiders into leaders of their former opponents, to raise up and renew us from unexpected directions, that is proof that the Spirit of God is still active and alive in these days.