The Bush administration took a beating Tuesday from farm-state senators angry about a pending trade agreement with Central America. A Republican who supports the deal said the administration hadn't done enough to show farmers how they would benefit.

The Central America Free Trade Agreement would phase out protective tariffs and quotas in the Dominican Republican and Central American countries as well as the United States.

"They're going to have to put on a full-court press, or CAFTA may not pass," said Sen. Pat Roberts, R-Kan. "They're going to have to sell it a lot better and prove to a farmer or rancher how he or she is really benefiting from this."

Roberts said farmers have "trade fatigue" because earlier deals were both oversold and overcriticized. Now producers, such as sugar growers, are demanding to see what the deal offers their specific commodity, he said.

Sugar growers have created the most opposition to CAFTA on Capitol Hill. Republicans from sugar states joined Democrats in criticizing CAFTA during a Senate Agriculture Committee hearing Tuesday.

CAFTA would allow six countries — Costa Rica, the Dominican Republic, El Salvador, Guatemala, Honduras and Nicaragua — to ship more sugar to the United States. The trade deal has special clauses limiting that amount, but U.S. sugar growers say any increase will devastate their market.

If the agreement is so badly needed, then "why take a relatively little thing like sugar and put it in there?" asked Sen. Craig Thomas, R-Wyo.

Wyoming growers are storing sugar because they can't sell it right now, Thomas said.

Sen. Norm Coleman, R-Minn., said 40,000 Minnesotans depend on his state's sugar industry. "I've got folks who their economic future is as tied to this as any of the poor folks living in Central America," Coleman said.

Agriculture Secretary Mike Johanns defended the deal, saying it would allow the six countries to ship about one day's worth of U.S. production into this market.

"Basically, the impact on the U.S. sugar industry will be minimal," he said.

Johanns warned that the Central America agreement is crucial to the World Trade Organization's current "Doha round" of global trade negotiations.

If CAFTA fails, "all of a sudden we're going to have a very tough time negotiating," Johanns said.

Thomas and Coleman have not decided how they will vote on CAFTA. The agriculture committee's chairman, Sen. Saxby Chambliss, R-Ga., has said he plans to vote against the agreement as it stands.

The agreement was negotiated more than a year ago and President Bush is pushing Congress to approve it before taking a monthlong vacation in August. However, opponents in the House claim they now have the votes to defeat it, and Republican supporters have said a vote won't occur as long as that situation exists.