Has a third party ever ran two former statewide office holders on a national ticket since Teddy Roosevelt? Two former GOP Governors, pretty impressive ticket. Could be a legitimate option for many Republicans, don't know what kind of Republicans exactly tho (you'd think #NeverTrumps, and most would be, but I can imagine a lot of very conservative Republicans would not vote for a libertarian and a moderate/RINO).
The 1924 Progressive Party ran Sen. Robert M. Lafollette (R-WI) and Sen Burton K. Wheeler (D-MT) and carried a number of states.
The 1948 Dixiecrats had two (2) sitting Governors, Strom Thurmond (D-SC) and Fielding Wright (D-MS).
The 1948 Progressive Party had former VP Henry A. Wallace (D) and Sen. Glen Taylor (D-MT).
The 1968 American Independent Party had Gov. George Wallace (D-AL) and Gov. S. Marvin Griffin (D-GA). Griffin was the name that appeared on the ballot in most states; he was a stand-in for Gen. Curtis Lemay, who was named as Wallace's VP pick
Rep. John Anderson (R-IL) was not a statewide candidate, but he had won a significant number of delegates in 1980 and was a prominent House Republican when he ran an Independent bid for President in 1980. Gov. Patrick Lucey (D-WI) was his running-mate.