On Day 15 of Ramon Saul Sanchez's water-only hunger strike -- called to free a fishing boat, the Human Rights, from a Key West dry-dock -- the dirt lot opposite Miami's Claude Pepper Federal Building looked like a full-blown South Florida festival.

Trucks careened past bearing Cuban and U.S. flags. Pension-age exiles wearing caps and T-shirts of Sanchez's Movimiento Democracia and Alpha 66 crammed around a 12-by-12-foot tent. Inside, Sanchez, 44, sat wearily in a recliner, next to the cot where he has slept since declaring the strike, shunning all but water.

The tent is decorated with a photo of Jose Marti, a poster of Martin Luther King Jr., religious items, a scale, a portable toilet -- and a huge sign declaring the U.S. government's seizure of the 35-foot fishing boat ``an infamy -- MacCarthyism [sic] at its worst.''

At issue: The U.S. government's Dec. 10 decision to seize Human Rights, one of the movement's two boats. Sanchez wants it back; he vows not to take sustenance until the Coast Guard releases it.

A former gun-toting commando who now advocates nonviolent change on the island, Sanchez lost the ship at sea because he refused to pledge that he would not take it into Cuban waters.

He started the hunger strike at 10:30 a.m. May 5 after a robust breakfast of black beans, rice and picadillo, the traditional Cuban ground beef dish. He weighed 224 at the time and is now down to 198, he said.

``This has been such a spiritually rewarding experience, even though physically it might be a little bit harsh,'' Sanchez said Wednesday morning while supporters gathered signatures for letters to President Clinton urging the boat's release.

He got dewy-eyed when a letter arrived from the Information Bureau of Human Rights in Cuba declaring that the Havana-based Directorate for Political Prisoners and Former Political Prisoners of Cuba supports his effort.

``How far is this administration going to take this policy of being the bodyguard of the Castro regime?'' Republican Congressman Lincoln Diaz-Balart asked. ``They not only prevent armed action against Castro, they prevent people like [Brothers to the Rescue founder Jose] Basulto and Sanchez from carrying out peaceful protests. It's unconscionable.''

Diaz-Balart, who spoke from Washington, has visited Sanchez twice during the hunger strike and characterizes the seizure of the vessel as ``unconstitutional.''

``The question is, are they going to wait until Ramon Saul Sanchez dies before they release the boat? That would mean eternal shame on them. I hope and pray that they act, as I have demanded on the House floor.''

The Clinton administration has periodically invoked extraordinary maritime powers to clamp down on Sanchez's protests at sea in the aftermath of Cuba's February 1996 shootdown of two Brothers planes that left four men dead. Sanchez said he started the hunger strike after less-public efforts to pressure the U.S. government failed.

Besides seeking the return of the boat, he said his fast should also demonstrate the power of peaceful protest to democratic forces on the island.

``The boat is a symbol of freedom, of human rights, of civil rights,'' he said. ``It's the principle.''

Ever since Sanchez got the city permit to hold the demonstration and set up the carpeted tent in the park opposite the Miami-Dade Cultural Center, his hunger strike headquarters have increasingly become a pilgrimage point for Cuban activists.

Elderly Cubans rallied around the tent early Wednesday, urging passersby to sign the letters to the President. A few handed cash to volunteers in Democracy Movement T-shirts to help offset costs, although fund raising is frowned upon at the site, spokesman Luis Felipe Rojas said.

Sanchez stays there around the clock but never alone, Rojas said.

Friends, family and movement members sit vigil with him. Crowds gather around past midnight. Downtown homeless people have also dropped by, Sanchez said. One presented him with a long-obsolete hotel key as a good-luck charm.