For several decades, the association of the Republican Party with the Civil War and Reconstruction in the South relegated meaningful political participation and competition to the Democratic Party. This one-party rule in Texas and the South resulted in factionalism within the Democratic Party and a heavy emphasis on racial politics meant to attract conservative white voters and suppress black political participation. The chart uses midterm election turnout to illustrate the decline of Democratic dominance. Before party competition began to develop in the 1950s, voters recognized that the real electoral choices that filled every public office except the presidency were made in the Democratic primary, not the general election. But party competition increased in the 1950s and early 1960s as Democratic factionalism, the politics of civil rights, and socio-economic change eroded Democratic dominance in Texas. The watershed event came in 1961. Republican John Tower won a U.S. Senate seat in a special election to replace Lyndon Johnson who had become Vice-President. Tower's election signaled the return of two-party competition to Texas. General election turnout surpassed Democratic primary turnout in the next midterm election in 1962, and never again fell below primary turnout.
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