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The first movement was "Jacksonian democracy," the expansion of voting rights at least among white men under the presidency of Andrew Jackson in the early nineteenth century -- this largely removed property restrictions, thus ensuring that white men who were poor or recent immigrants would be able to vote. In the mid-nineteenth century, the U.S. Civil War would result in larger changes to the Constitution which ultimately affected voting. The Fifteenth Amendment, passed in the wake of the Civil War, states that voting rights cannot be restricted or denied based on "race, color, or previous condition of servitude" -- meaning that the franchise was ultimately extended to former slaves. In practice, however, the former slave states would find various ways to restrict voting opportunity (through various "Jim Crow" type laws, which would create artificial obstacles on the local level to prevent ex-slaves from voting) for African-Americans until the latter half of the twentieth century. This racial bias would require certain other remedies including another Constitutional Amendment outlawing poll taxes (the Twenty-Fourth Amendment in 1964); various legislative remedies for racial minorities to guarantee their rights all too often trampled on by state governments in the south (with the Voting Rights Act); and Supreme Court decisions (which would remove various tactics designed to prevent minorities from voting, like the "grandfather clause," the "white primary," or literacy tests).

Numerically speaking, perhaps the largest single extension of the franchise came with the passage of the Nineteenth Amendment in 1920, which declared that voting could not be denied "on account of sex" -- thus extending the franchise to women (i.e., half of the adult human population of America). Other constitutional amendments expanded voting rights in other ways -- for example the Seventeenth Amendment changed the Constitution's original method of electing senators, and allowed them to be elected directly by popular vote. The Twenty-Sixth Amendment in 1971 would ultimately set in place a uniform age designation -- anyone over the age of 18 could not be denied the right to vote because of age. (Previously age restrictions for voting had been set individually by the states). Overall, by the start of the twentieth century, various changes -- through the activism of individuals, and through Constitutional amendment, legislation, and judicial decision -- had expanded the franchise to make it substantially larger than it initially was in the Constitution's original intent.

Although these various provisions make it sound like the franchise has been broadly extended in the United States, but some inequalities persist. Many states, for example, deny voting rights to convicted felons -- considering the outlandish rates at which America imprisons people, and the overwhelming racial imbalance in that population of prisoners and convicted felons, it might appear that in a certain sense the various Jim Crow-type provisions to block African-Americans from voting have been perpetuated in a disguised form.