WASHINGTON – The House narrowly approved the Central American Free Trade Agreement early today, a personal triumph for President Bush, who campaigned aggressively for the accord he said would foster prosperity and democracy in the hemisphere.

The 217-215 vote just after midnight adds six Latin American countries to the growing lists of nations with free trade agreements with America and averts what could have been a major embarrassment for the Bush administration.

It was an uphill effort to win a majority, with Mr. Bush traveling to Capitol Hill earlier in the day to appeal to wavering Republicans to support a deal he said was critical to national security.

Lobbying continued right up to the vote, with Vice President Cheney, U.S. Trade Representative Rob Portman, and Commerce Secretary Carlos Gutierrez tracking undecided lawmakers.

America signed the accord, known as Cafta, a year ago with Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and the Dominican Republic, and the Senate approved it last month. It now goes to the president for his signature.

To capture a majority, supporters had to overcome what some have called free trade fatigue, a growing sentiment that free trade deals such as the North American Free Trade Agreement with Mexico and Canada have contributed to a loss of well-paying American jobs and the soaring trade deficit.

Democrats, who were overwhelmingly against Cafta, also argued that its labor rights provisions were weak and would result in exploitation of workers in Central America. But supporters pointed out that CAFTA would over time eliminate tariffs and other trade barriers that impede American sales to the region, correcting the current situation in which 80% of Central American goods enter America duty-free but Americans must pay heavy tariffs.

The agreement would also strengthen intellectual property protections and make it easier for Americans to invest in the region.

“This is a test of American leadership in a changing world,” Rep. Kevin Brady, a Republican of Texas and a leading proponent of the agreement, said. “We cannot claim to be fighting for American jobs and yet turn our backs on 44 million new customers in Central America.

In the end, it was the national security argument – that rejection of the deal would further impoverish the region, undermine their democracies, and exacerbate the flow of illegal immigrants into America – that appeared to persuade some wavering members.

The president, White House press secretary Scott McClellan said, stressed to Republicans “the importance of supporting young and emerging democracies in our own hemisphere, and the importance of strengthening democracy here in our own hemisphere. And that was something that clearly resonated with members of the House.”

“It is good for our national security in supporting these fledgling democracies at our back door,” the House majority leader, Tom DeLay, a Republican of Texas, said after the meeting with Mr. Bush.

To allay lawmakers’ concerns about the American sugar and textile industries, the administration also won over several Republicans by pledging protection from Central American imports.

The House on Wednesday also passed legislation strengthening the monitoring of China’s trade policies, a bill that GOP leaders brought to the floor to satisfy several lawmakers who were undecided on Cafta because they said America wasn’t tough enough in enforcing trade laws.