I've been reading Michael Kazin's book A Godly Hero about William Jennings Bryan instead of studying economics (I'll let you know how that works out for me after my exam in Money and Banking tomorrow), and I think there should be "presidential" libraries for Will Bryan and for Barry Goldwater.
These two men dramatically altered the American political landscape just by running for president, even though they were never elected. There are many men who actually win who don't have as great an impact as these two. Without Bryan, there is no FDR, no LBJ, no HRC. Without Goldwater, there is no Reagan or Bush (when Bush feels like it).
So I think the National Archives should open branches in Lincoln, Nebraska and Phoenix, Arizona combined with museums to these two guys. Isn't that what they did at the new Lincoln museum in Springfield, Illinois?