The onset of the
Great Depression undermined the confidence of business in Republican promises of prosperity. The four consecutive elections of Franklin D. Roosevelt delivered the Democrats virtually uncontested dominance. By the time of their sweeping victory in
1936, the Party had become dominated by the
New Deal Coalition, remaining unchallenged until
Dwight D. Eisenhower led Republicans to victory in 1952. Throughout the 1930s and 1940s,
third parties such as the
Minnesota Farmer–Labor Party,
Wisconsin Progressive Party, and
Nonpartisan League saw renewed electoral success, most notably in the
Upper Midwest. In 1936, the
American Labor Party formed, and 1938 saw the
National Progressives of America emerge out of the Wisconsin Progressive Party. Despite the power of the New Dealers, the
conservative coalition, comprising northern Republicans and southern Democrats, generally controlled Congress from 1938 to 1964. Nevertheless, the New Deal Coalition quickly grew to include a range of politicians unusual at the time for its diversity. Although still broadly consisting of the
White Anglo-Saxon Protestants who dominated the conservative coalition as well, New Dealers also grew to include new ethno-religious constituencies, such as Catholics and Jews, in addition to liberal White southerners,
trade unionists, urban
machinists, progressive intellectuals, populist farm groups, and even some ex-Republicans from the
Northeast. These groups all became primary voting blocs of the Democratic Party that are still dominant in the modern era. The Republican Party underwent a dramatic ideological change of its own during this period, consisting of a conservative wing led by Senator
Robert A. Taft and then
Barry Goldwater, and a moderate to liberal wing led by
Thomas Dewey,
Nelson Rockefeller,
Earl Warren,
Jacob Javits,
George W. Romney,
William Scranton,
Henry Cabot Lodge Jr., and
Prescott Bush. The liberal wing experienced more electoral victories than the conservatives until the election of
Richard Nixon in
1968, marking conservative Republicans' first major victory, as Eisenhower had been more aligned with the Party's liberal wing. Despite his rhetoric, Nixon continued and expanded on liberal policies stating in 1971 "
We are all Keynesians now". However, Nixon's implication in the
Watergate scandal ruined him and badly damaged public perception of the Republican Party nationwide until
1980, when
Ronald Reagan was elected president and successfully revitalized the party. With his ascension, Reagan effectively swept away the last remnants of the party's liberal wing, who had all switched to the Democratic Party by this time. For this reason, Reagan's election is widely regarded as marking the end of the Fifth Party System and the beginning of the Sixth Party System that arguably continues today. ==Analysis==