This comparison grows more popular the longer it's repeated.
To quote a fictional german Nazi: "You really think we'd make a nigger our Führer!?"
The Obama/Hitler comparison is major bollocks.
And regarding town hall "protesters" comparing the health care reform to "something that could have origined in early 30's germany":
We evil germans got nationalized health care since 1883 courtesy of Fürst Otto von Bismarck.