WASHINGTON (AP) _ Lawmakers agonizing over how to vote on the North American Free Trade Agreement felt the pressure of boisterous constituents, even as they met behind closed doors.

Until now, members of Florida's 23-member House delegation, one of the chamber's biggest, had been heavily against the agreement. But some were believed to be reconsidering in the wake of side deals protecting citrus products, sugar, tomato and other vegetables.

As they filed into a Capitol meeting room, about a dozen NAFTA opponents from Ross Perot's United We Stand pointed fingers and shouted slogans at them, such as, ''Don't change your minds.''

Some even tried barging into the room when the door opened to admit lawmakers. They were finally prodded away by police officers.

Afterward, Rep. Alcee Hastings, D-Fla., said the angry reaction by the Perot backers was nothing new. ''And I couldn't give less than a hoot about their hootin','' he said.

---

Leave it to the House of Representatives to serve up a few labored metaphors at times like this. Like the pep talk Rep. Peter DeFazio, D-Ore., gave his colleagues at the outset of Tuesday's floor session.

Displaying four bulky paperback books containing the implementing legislation for NAFTA, he likened the measure to a turkey. ''It needs some dressing up,'' DeFazio said. ''There it is, a 15-pound turkey. The side agreements (on labor and environmental protections) aren't even going to be on the table ... when we sit down to feast on NAFTA.

'' ... So if you predicated your agreement (to vote 'yes') on these side agreements,'' he added, ''you won't be celebrating Thanksgiving.... You will be celebrating April Fool's Day.''

---

And then there was Rep. Jim Traficant, D-Ohio, to keep the rhetoric rolling.

''People say this will be good for the alien problem,'' he said. ''That's right. Americans will be jumping the border trying to get jobs down in Mexico.''

''People say this will be good for the farmer. That's right. American farmers will be pumping out welfare cheese day and night folks.''

''I liken NAFTA to putting (heavyweight boxing champion) Evander Holyfield in the ring with that Mexican lightweight champion....and then tying his hands behind his back and putting shackles on his leg.''

---

How important is the NAFTA vote? Historic, if you believe radio advertisements by USA-NAFTA, a business group that supports the trade pact.

''Once in a generation there are votes in our Congress which shape America's future: the Louisiana Purchase, the Marshall Plan, the 1964 Civil Rights Act,'' the ad intones.

''These votes came down to a fundamental choice about the future of our country - would we accept the facts of change....or give in to the forces of fear?''

---

Notwithstanding the ferocious House debate over the trade pact, Senate Majority Leader George Mitchell said the treaty is a cinch for passage on his side of Capitol Hill.

''Let me make it clear and unmistakable. The Senate will pass the North American Free Trade Agreement. Let there be no uncertainty about that,'' said Mitchell, noting that the pact will next be taken up in the chamber if it clears the House.

''If Congress approves this agreement, the United States will affirm its leadership role in this hemisphere and around the world....If the United States does not capitalize on this opportunity, our competitors will.''

His Republican counterpart, Sen. Bob Dole, shared Mitchell's sentiments.

''Nobody wants to knowingly put anybody out of work. We all want to create jobs,'' the Kansas senator said. ''It just seems to me we don't want ....to retreat from the marketplace. We don't want to huddle on the sidelines.''