Lobbyists for a day, six Latin American presidents are making a rare joint trek to the Capitol, trying to convince U.S. lawmakers that a free trade agreement linking the United States with their countries is in everyone's best interest.

President Bush's call for reinforcements from overseas still might not carry the day. There is heavy opposition to the Central American Free Trade Agreement from U.S. labor unions, sugar farmers and groups upset with America's soaring trade deficits.

U.S. Trade Representative Rob Portman said the Latin American leaders have been asked to come to Washington so U.S. lawmakers can hear firsthand what a free trade deal could do in terms of promoting economic growth in their nations.

"They are going to talk about the importance of this agreement to stability and democracy in these countries," Portman told reporters Tuesday after a CAFTA strategy session with Republican lawmakers at the Capitol.

The presidents of the Dominican Republic and the five Central American countries of Costa Rica, El Salvador, Guatemala, Honduras and Nicaragua are expected to expend plenty of shoe leather walking the halls of Congress, with meetings scheduled throughout the day Wednesday in an effort to generate support.

Meetings are scheduled with Senate Republican Leader Bill Frist and House Speaker Dennis Hastert as well as key members of both chambers on trade issues.

Unusual effort

No one could remember a similar approach to Congress by so many foreign leaders at the same time. "We haven't been able to come up with anything comparable to this," said Senate historian Donald Ritchie. "It is unusual for any head of state to lobby Congress, but even more unusual for a half-dozen to do it."

The foreign leaders' visits will be capped off with a meeting with Bush on Thursday at the White House, an event the administration is hoping will demonstrate the president's strong involvement in the coming legislative fight.

Even before the presidents arrived in Washington, the administration had them hop-scotching the country talking to governors in key states, participating in rallies and meeting with newspaper editorial boards.

Salvadoran President Tony Saca, one of America's strongest allies in Central America, touched down in Los Angeles, San Diego and Santa Fe, New Mexico, on his way to Washington.

Three other leaders -- presidents Enrique Bolanos of Nicaragua, Ricardo Maduro of Honduras and Oscar Berger of Guatemala -- participated in an event Monday at the Port of Miami with Florida Gov. Jeb Bush.

Maduro said the poor of their countries needed to see more tangible benefits from democracy.

"That means sustained, significant and equitable economic growth, and the only way we are going to be able to get that ... is by having trading partners like the U.S. under systems like CAFTA," the Honduran president said.

All the administration's activity underscores that it is still searching for the votes to pass the measure. The fight is shaping up to be the most ferocious free trade fight since the North American Free Trade Agreement linking the United States, Canada and Mexico was approved more than a decade ago.

Opponents contend that CAFTA, just like NAFTA, will allow American companies to move more of their manufacturing facilities out of the country to the CAFTA countries with their low wages and lax enforcement of environmental laws.

Anti-CAFTA forces held a rally Tuesday on Capitol Hill where AFL-CIO Secretary Treasurer Richard Trumka told the crowd, "From timber in Washington to computer engineering in Massachusetts, and every type of job in between, America is losing good jobs due to bad trade deals."

The CAFTA deal faces more trouble because of strong opposition from U.S. sugar producers. They are upset that the deal will allow increased imports of sugar from the Latin American nations.