Their relationship has echoes of the dynamics between Senate Majority Leader Lyndon Johnson and northern liberals in the 1950s.

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Conservative southern Democrats, alienated by the growing influence in their party of minorities and northern liberals, began to cast ballots for Republicans throughout the South.

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Moreover, this new majority, if it emerges, will be much more ideologically cohesive than the Democratic majority of Bill Clinton's first two years, which was an uneasy alliance between Northern liberals and conservative Southerners.

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Johnson constantly warned conservative southern Democrats that if they did not compromise on issues like civil rights he would not be able to contain northern liberals like Illinois Senator Paul Douglas who were pushing for much bolder changes.

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