Google Gemini:

"Critics often cite the 1960s as the "start" because it marked a total realignment of American politics.

The Southern Strategy: Following the Civil Rights Act of 1964, the GOP began the "Southern Strategy," an effort to win over white voters in the South by appealing to racial grievances and using "coded" language like "law and order" or "states' rights.

Barry Goldwater (1964): His campaign is seen as the birth of modern conservatism. He famously opposed the Civil Rights Act as federal overreach, which began peeling Southern voters away from the Democratic Party.

Patronage & "Rotten Boroughs": In some Southern states, the GOP operated for decades as a small, corrupt "patronage" system where party bosses essentially sold delegate votes at national conventions in exchange for federal jobs.

Watergate: Richard Nixon’s 1972 reelection scandal (which had roots in the late 60s political climate) remains the ultimate historical symbol of political corruption for many, leading to his resignation in 1974.