Puerto Ricans voted 58.6% for statehood in November 2024, their seventh referendum on the question. Congress hasn't acted on it. Article IV gives Congress sole power to admit new states with a simple majority vote in both chambers—no constitutional amendment needed, no supermajority required. Congress can admit a territory whenever it wants, or never.
Washington D.C. statehood faces similar gridlock despite its more than 700,000 residents having no voting representation in Congress. The Constitution sets only one real limit on admission—you can't carve a new state out of an existing state without that state's permission. Otherwise, admission is pure politics, and the 3.2 million American citizens in Puerto Rico have no vote in Congress to force the issue.