Answer:
Because both parties had reformist and modifying views and proposals in all sectors of American society.
Step-by-step explanation:
Although the Republican and Democratic parties have ideological differences, both are part of the progressive tendencies that have been established in the USA. These trends were aimed at promoting reforms not only in American politics, but in all sectors of society, leading the USA to progress, properly speaking. These reforms were, primarily, related to reforms in economic policies, but it acted in reforms brought about by the modernization of the country, combating corruption, economic production, security and rights, management of natural resources, among others.