In 1893, the United States experienced a "panic" or what we would today call a depression or a severe recession. The panic began in 1893 when wheat prices crashed and lasted for four years, affecting the entire economy. As banks began to fail in those days before the government insured deposits, people made runs on banks to withdraw their money while they still could. Railroads failed, unemployment spiked and at same time many people saw their life's savings wiped out from the collapse of the banking sector. This led to middle class families not being able to make their mortgage payments and losing their homes to foreclosure.
Ordinary people who suffered under the harsh economic conditions became angry at what they saw as corruption among the global financial elite. Into this picture walked populists like Mary Lease and William Jennings Bryan, who appealed to the discontented farmers at a time when the U.S. economy was much more agrarian based than today.
Mary Lease of the Populist Party was a fiery speaker who blamed Wall Street for the troubles that plagued Kansas farmers. She said
Wall Street owns the country. It is no longer a government of the people, by the people, and for the people, but a government of Wall Street, by Wall Street and for Wall Street....
William Jennings Bryan of Nebraska was also an orator who spoke in riveting terms to the widespread discontent of common people. He advocated for setting up a silver standard in addition to the gold standard so as to increase the money supply and increase inflation. Many farmers believed this would allow them to get out from under the mountains of debt caused by the collapse of wheat prices.
The important point is that in times of economic panic and uncertainty, people are more willing to listen to compelling speakers who seem to offer new solutions to economic problems and who appear to have the interests of the common person at heart. While not all the ideas of these populists were sound, many were: the United States needed to institute financial reforms to curb the power of the Gilded Era robber barons and to begin to create a safety net under its people. In such a period of churn as the 1890s, citizens became open to ideas and speakers that in other periods might have seemed radical.
Mary Lease and William Jennings Bryan are both associated with the agrarian Populist movement of the late nineteenth century, though the two were involved in the movement to different degrees. Lease was involved in the movement from its early days, working for the the Farmers' Alliance as a leading speaker and agitator in the campaign in Kansas. Supposedly urging farmers to raise "less corn and more hell," she focused on building a sort of class-consciousness among midwestern farmers, who were beset on all sides with economic difficulties. Bryan, on the other hand, was a Democratic politician who ran for President in 1896. Also a Kansan, he adopted many aspects of the Populist movement into the Democratic platform, most famously the unlimited coinage of silver (which would expand the money supply, long a demand of farmers.) Like Lease, he had a knack for oratory and memorable phrases, famously proclaiming that the bankers and financiers of the nation "shall no crucify mankind on a cross of gold." Ultimately, both Bryan and Lease appealed to farmers because they had a knack for elevating complex issues (like monetary policy) into simple moral questions. They consistently pointed to the larger forces in government and finance that victimized farmers, and made a persuasive case that farmers (and in Bryan's case, labor as well) had to vote and act as a political bloc in order to protect their own interests.