From wiki:
The 1904 election was rife with fraud and controversy. Alva Adams won election, but soon after he took office the Republican legislature declared James Peabody to be the actual winner, on the condition that Peabody immediately resign. Since Peabody had been governor for a few moments before resigning, it was his lieutenant governor, Jesse McDonald, that succeeded to the governorship. In all, Colorado had three governors on March 17, 1905.
What i want to know is, a) was this election really that much worse compared to other early 20C western elections and b) how was this solution viewed by the public and legal establishment. Was McDonald viewed as illegitimate?
I don't have B, but I can provide another example of this happening -- Georgia's "Three Governors Controversy".
The state of Georgia had a similar crisis in 1946-47. The winner of the election, Eugene Talmadge (a long-time figure in GA politics), died before being sworn in, and his party arranged for the state legislature to elect the governor. This was possible because of ambiguities in the new state constitution (which stated that the lieutenant governor would succeed a sitting governor), and the legislature elected Talmadge's son, Herman in January of 1947. After this, the lieutenant governor-elect Melvin Thompson filed suit for the governorship.
Meanwhile, the outgoing governor Ellis Arnall refused to leave office until it was clear who the rightful new governor was. However, Talmadge had the locks changed in the governor's office, leading Arnall to set up a governor's office-in-exile in the lobby of the capitol building. Arnall eventually gave up his claim and supported Thompson.
So it was then down to two governors, who both were attempting to run the state. In March, the Georgia Supreme Court ruled in favor of Thompson, leaving him as acting governor until a special election to fill the post could be held.
Talmadge won the election, so there's that.
SOURCE: New Georgia Encyclopedia "Three Governors Controversy" http://www.georgiaencyclopedia.org/articles/government-politics/three-governors-controversy