Elections in the US are administered by states and thousands of local jurisdictions, producing wide variation in registration, voting methods, and verification. Debate centers on where the balance between access and verification should sit.
There is no single national election system. States set their own rules on registration deadlines, early voting, mail ballots, and identification, within federal constraints such as the Voting Rights Act and the National Voter Registration Act.
Documented cases of in-person impersonation fraud are rare in audits and prosecutions. Election officials and researchers more often identify administrative errors, voter roll maintenance issues, and problems with mail ballot handling as practical vulnerabilities.
Redistricting is a related and distinct fight. District lines drawn by legislatures, commissions, or courts shape which votes are competitive, and both major parties have drawn favorable maps where they hold the power to do so.