Which leader's influence is most closely associated with the introduction of a more direct election process, an increase in presidential power using vetoes, and a complex interplay between federal and state powers that continue to affect contemporary debates?

Andrew Jackson is most closely associated with expanding popular participation in presidential elections and strengthening the presidency. He used the veto more aggressively than earlier presidents, treating it as a tool to shape policy, and his conflicts over federal authority and states’ rights—especially during the Nullification Crisis—remain relevant to debates about the balance of power. Therefore, the correct choice is Andrew Jackson.

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