180+ wins, .640+ W-L% (pitchers who started career in 1900 or later)
Mordecai "Three Finger" Brown
Active pitchers:140 W, .620 W-L%:
Andy Pettitte: 240 wins, .637 W-L%
Roy Halladay: 163, .660
Tim Hudson: 162, .661
C.C. Sabathia: 151, .637
Roy Oswalt: 144, .634
6 of the pitchers on the top list are in the Hall of Fame, with Randy Johnson, Pedro Martinez and Roger Clemens still a few years away from eligibility. 8 of the 9 pitchers won at least 219 games, but Lefty Gomez won only 189 and still made the Hall of Fame (Veteran's Committee, 1972).
None of the 5 active pitchers are locks for the Hall of Fame yet. Pettitte's career ERA is almost 4.00 and he admitted to using HGH. Halladay is clearly one of the best pitchers of his generation, and is seen as a throw back, which will probably help. The problem is that he's already 33 and only has 163 wins.
Voters have been reluctant to elect starting pitchers who failed to reach 300 wins, but that view will have to change eventually as fewer star pitchers even get close to that number.
Tim Hudson had a great start to his career, but hasn't received a Cy Young vote since 2003 and it already 35. He will finish with excellent numbers, but isn't a Hall of Famer. Sabathia is only 30 and should win a lot of games pitching for the Yankees, and should have many chances for postseason glory. We'll have to check back on him in a few years, but he has a shot.
As for Oswalt, there have been rumors of early retirement for years, so it's hard to see him hanging around long enough to reach 200 wins. He also hasn't been the same since 2005 or 2006, although he was very good until 2008.