More than 360,000 voters have turned out for Puerto Rico's first national Democratic Party primary, a resounding affirmation of continued ties with the United States.

The pro-statehood faction of the party had contended that a vote in the primary was a vote for continued U.S. citizenship, statehood and federal benefits. Pro-statehood leaders had predicted a showing of about 200,000.

Voters interviewed as they were leaving the polls made such statements as: "This means being an American citizen," "This is the first time Puerto Rico has an opportunity to express itself in national politics," and, "We owe our progress to the United States and I want to strengthen the bonds between us and them."

The primary marks the first time that local branches of both national parties, Republican and Democratic, are controlled by stateholders.

The Democratic Party branch has traditionally been controlled by party-to-party ties with the pro-commonwealth Popular Democratic Party. The PDP called on its members to boycott the primary several months ago, however, leaving the 22 pro-statehood candidates virtually unopposed.

The victorious stateholders will now serve as delegates to the Democratic Party's midterm convention in Nashville.

The victory may have little other practical significance for the stateholders.

The crucial 1980 presidential primary may not materialize after a recent Commonwealth Supreme Court ruling that public funding of national primaries is unconstitutional. Raising enough private funds for the highly contested 1980 primary would be almost impossible, observers say.

Pro-statehood governor Carlos Romero Barcelo is expected to appeal the ruling to the U.S. Supreme Court.

Furthermore, although stateholders have not had nominal control of the Democratic Party until now, they have actually been the recipients of political favors from Washington during the Carter presidency.

The pro-statehood faction backed Carter, during Democratic Party caucuses in 1976, while the pro-commonwealth faction supported Sen. Henry M. Jackson (D-Wash).