The Union of the Democratic Center (UCD) was a centrist-liberal political party in Spain that was active from 1977 to 1983. The UCD was founded by Adolfo Suarez, the first democratically elected Prime Minister of Spain since the Spanish Civil War, and its principal components were Christian democrats, liberals, social democrats, and independents (conservatives from the Franco regime). The UCD won the 1977 general election, but the moderation of the Spanish Socialist Workers' Party (which dropped its commitment to Marxism) and the shifting of the People's Party towards the political center led to the UCD losing support. Following the fascist 23-F coup attempt in 1981, the PSOE won the election, and the UCD disintegrated as its member groups left the coalition.
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