In researching my answer to Can electors "flip the ticket?", I re-examined the results of the election of 1872. As stated in that answer, 1872 was an interesting election, not for the result (Grant beat Greeley decisively), but rather for the allocation of Greeley's votes. Three days after the popular election, Greeley went crazy. Within a month, he was dead.
When the electoral college met, Greeley's electors were essentially unpledged - the three that voted for Greeley ultimately had their votes invalidated. Eighteen of them did I what would have expected - they voted for Benjamin Brown, the Vice Presidential candidate. What I don't get is why 42 of them voted for Thomas Hendricks. Hendricks was not nominated by the Liberal Republican or Democratic parties (Greeley was running on behalf of both). Indeed, everything I read on the internet says that he was mostly focused on getting elected as governor of Indiana.
Hendricks later went on to become Samuel J. Tilden's VP running mate in 1876 (the one time I believe the electoral result truly was stolen), and eventually became Grover Cleveland's Vice President in 1884, just prior to Hendricks' death in 1885. Clearly, Hendricks' popularity was on the ascendent - but what compelled the electors to select him as Greeley's replacement?
Why the sudden upswell of votes for a guy who wasn't even on the ticket?