For nearly 100 years likely Republican candidates for office in Vermont agreed to abide by the Mountain Rule in the interests of party unity.

Several factors led to the eventual weakening of the Mountain Rule, including: the longtime political dispute between the Proctor (conservative) and Aiken-Gibson (liberal) wings of the party; primaries rather than conventions to select nominees; the direct election of U.S.

In the 1960s the rise of the Vermont Democratic Party and the construction of Interstate 89 also contributed to the end of the Mountain Rule.

[11] In November 1927, Lieutenant Governor Hollister Jackson died in the Great Vermont Flood of 1927, and the position remained vacant until Stanley C. Wilson took office in January 1929.

[10] The lieutenant governorship remained vacant until Snelling's widow Barbara, the winner of the 1992 election, took office in January 1993.