Longest Streak of Bellwether Counties?

[electionsguy259]

Hey guys

Happy to join the forum, I've seen a lot of really interesting election analyses on here.

For this forum, my main question is about bellwether counties. I know that Clallam County, Washington has been the nation's most reliable bellwether county since 2020, and prior to that was Valencia County, New Mexico. Does anyone know which county held the longest streak prior to Valencia County? I can only find Okanogan County, Washington, whose streak began in 1904 and ended in 1996 when the county voted for Bob Dole.

[Schiff for Senate]

No, but these are some (formerly) bellwether counties (they voted for the winner in every election from at least 1980 onwards, except in 2016 or 2020: Bexar, TX (voted for Clinton after only backing the winner in every election from 1972 onwards); Buncombe, NC (streak from 1964-2012); Centre, PA, Clackamas, OR, DeKalb, IL (from 1980-2012); Merced, CA (1972-2012); San Bernardino and San Joaquin, CA, and Skagit, WA (1980-2012); Stanislaus, CA and Sandoval, NM (1972-2012); Ventura, CA and Will and Winnebago, IL (1980-2012); Bremer, IA, Essex, VT and Cortland, NY (1980-2016); Hidalgo, NM (1972-2016); Juneau, WI (1960-2016); Marquette, WI and Otsego, NY (1980-2016); Ottawa, OH (voted the same as Ohio from 1944-present; it voted for the winner from 1964-2016); Richland, WI (1980-2016); Sawyer (1964-2016); Shiawassee and Van Buren, MI (1980-2016); Valencia, NM (1952-2016); Vigo (1956-2016); Warren, IL (1980-2016); Washington, ME (1980-2016); Westmoreland, VA (1964-2016); and Wood, OH (1980-2016).
 19 counties (named above along with some others) voted correctly in all presidential elections from 1980-2016 (inclusive). However, 18 of them voted for Trump in 2020 - leaving just one, Clallam, as both the only county that voted for the winner in every presidential election from 1980 onwards, and the county with the longest presidential streak.

 Regarding your question about what county held the streak before Valencia... that I don't know.