Question

Why was the political system so slow to respond to the economic grievances of farmers and workers>

Answer 1

The 1890's occurred in the wake of the American Civil War. Many federal politicians were engaged in reconstruction and efforts to bring the nation back together north-south.
Those of wealth who owned the railways, mines and factories also had begun to engage in lobbying with those in government. Any rumours of rumblings and mumblings by those in the less populated regions of the west or who lived in 'company towns [where voices were muted by industrialists and managers]' were not taken seriously.
Such complaints as lack of services, gouging of prices paid for local products and costs for finished goods coming to these people were basically ignored because, in part, they resided in less densely populated regions of the country.
As the population grew, along with the level of education of these residents, they began to find a voice. The Populists and the related Grangers began to send a message which those entrenched in office had to hear and respond to out of fear of being thrown out of office. There may have been the subtle threat in some people's minds that there could be another split in the Union - this time between East and West.

Answer 2

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