Harry Jaffa is one of the foremost Lincoln apologists. To be truthful, there is some doubt that Hitler ever said that, and it is possible that Harry Jaffa is wrong. However, the Lincoln apologists stand squarely on the side of Jaffa.
Yes, I know about the Rauschning quote, but I consider its provenance to be dubious enough that I didn't pull it out to bludgeon spacecowboy with and get into a "Hitler agreed with your side!" "No, HItler agreed with your side!" argument. Spacecowboy's claim though, was that Hitler had praised Lincoln in Mein Kampf and approved of his actions in consolidating the federal government, when the passage makes clear he didn't even mention Lincoln.