Hayes is probably one of the least-known, but he’s not underrated. He was in a tough spot at a really tough time and didn’t really do much. Hayes wasn’t a bad President — he was a good manager and, quite frankly, from 1877-1881, just keeping the country moving forward after Reconstruction was a big enough job.
I think he’s rated right where he should be. In my rankings last year, I had him at #27 (of 43). In other rankings, I think Arthur Schlesinger, Sr. had him ranked too high — 13 of 29 in 1948 and 14 of 31 in 1962. More recent rankings are closer to what I have him at. In 1990, the Siena Institute had him at 23 of 40; in 1996, Arthur Schlesinger, Jr. had him ranked 23 of 39; C-SPAN’s Survery of Historians had him at 26 of 41 in 2000 and 33 of 42 in 2009; the Wall Street Journal had him ranked 24 of 40 in 2005; and the University of London’s U.S. Presidency Centre had him ranked 30 of 40 in 2011. I think he definitely fits right in the lower section of the average Presidents.