While making our way through "Passage of Power" -- the fourth book by Robert Caro focused President Lyndon B. Johnson -- a thought occurred to us: What's the single best biography about each of the 43 presidents?

That's where you all come in.

Obviously, picking the best of the best for Abraham Lincoln, George Washington or FDR is tougher than picking the best (only?) great biography of, say, William Henry Harrison. ("He died in 40 days!")

But, we have faith in our Fixistas. Over the next few days, we want to hear from you. In the comments section below, submit your nominations for the best biography of each -- or at least a couple -- presidents. We'll keep chipping away until we get at least one for every president at which point we'll post the full list on the Fix.

Deal? Deal.  Get to it!