After 1896, Democrats co-opted some of the farmer radicalism of the Populist Movement
Middle-class reformers of Progressive Movement belonged to both parties
But by the 1890s, the political alignments began to shift again. Northern farmers, upset with Republican policies, began searching for new political leadership. The new Populist Party briefly answered their needs. But in the election of 1896, the Democratic Party stole much of the Populists' support by piggybacking on the Populists' calls for the free coinage of silver (which would have caused inflation, allowing poor farmers to pay their debts more easily). During this election, the Democratic Party made huge strides toward re-establishing its national viability. At the same time, the Republican Party further distanced itself from the pro-agrarian policies that had marked its original growth in the 1860s. William McKinley, the Republican nominee, ran as the candidate of business, and his greatest support came from the urban northeast.
Still, we must avoid too narrowly characterizing the major parties during these years; the Republican party was not merely the party of eastern elites, and the Democratic party was not entirely the party of western common folks. While big business rallied behind McKinley in 1896, elements within the Republican Party also led the movement for economic and social reform known as Progressivism. Republicans like Theodore Roosevelt and Robert LaFollette campaigned for increased regulation of big business, the rights of workers to organize unions, and protection of consumers against impure and mislabeled products. But still, the Republican Party solidified its identity over the next several decades as the party of business while the Democrats increasingly drew support from less affluent and more recent members of American society.
Through most of the fourth party system, Republicans dominated national politics. Only one Democrat won the presidency between 1896 and 1932—and that president, Woodrow Wilson, only won the office in 1912 because his two immediate Republican predecessors, Teddy Roosevelt and William Howard Taft, both ran against him, splitting the Republican electorate and allowing Wilson to win the election with just 42% of the votes.