The Senate voted by a huge margin yesterday to normalize trade relations with China, capping one of the biggest legislative battles of the year and heightening the prospect of a historic economic opening by the world's most populous country.

The 83-15 vote sets the stage for China's accession to the World Trade Organization, possibly before the end of the year, as those advocating increased engagement with the communist giant overwhelmed critics who argued that the trade deal is an abandonment of democratic principles in the name of corporate profits.

The legislation, approved earlier this year by the House, now goes to the White House for President Clinton's signature. The president has made passage of the China trade bill one of his top priorities this year, hoping to cement a free-trade legacy for his presidency that began in 1993 with passage of the North American Free Trade Agreement with Mexico and Canada.

"This landmark agreement will extend economic prosperity at home and promote economic freedom in China, increasing the prospects for openness in China and a more peaceful future for all of us," Clinton told reporters at the White House.

The bill will end a 20-year practice under which Congress reviewed China's trade status on a year-to-year basis and instead will grant Beijing permanent normal trade relations, guaranteeing Chinese goods the same low-tariff access to the U.S. market as products from all but a handful of countries.

In exchange, China agreed to open up its vast market of 1.3 billion people to U.S. farm goods, cars, telecommunications equipment and an array of other products as part of last year's market-opening accord with the United States that created the conditions for its admission to the 138-nation WTO, the body that enforces the rules of global commerce.

The Senate vote followed a high-powered lobbying campaign by big business, organized labor, human rights and other organizations that are engaged in a broader debate on the pros and cons of increasing trade and globalization. It followed two weeks of debate in which the Senate's solid, pro-trade majority--under the watchful pressure of leading business organizations--turned back a succession of amendments aimed at addressing China's record on human rights, religious persecution, trade and weapons proliferation.

"I know there are legitimate concerns about this legislation and that there are those who are having to struggle with whether or not we can trust China to comply," declared Senate Majority Leader Trent Lott (R-Miss.). "But I also know it would be a tremendous mistake to ignore the advantages of this trade legislation."

The bill's opponents kept up their fight to the end, however. "I think the Senate is about to make a grave mistake," Sen. Robert C. Byrd (D-W.Va.) said shortly before the vote. Referring to the recently fired Indiana University basketball coach, Byrd said China has behaved "like the Bobby Knight of the international community" in its saber-rattling toward Taiwan, suppression of religious freedom and weapons exports.

Even so, only seven, largely pro-labor Democrats joined eight Republicans in opposing the trade bill. Two of the no votes came from Maryland's two Democratic senators, Paul S. Sarbanes and Barbara A. Mikulski, while Sens. John W. Warner (R) and Charles S. Robb (D) of Virginia voted in favor.

"I believe we should engage China--but not embrace China," Mikulski said in a statement.

The Senate battle was much less contentious than the earlier debate in the House, which approved the bill in May despite an aggressive drive by labor organizations and other leading Democratic constituencies to defeat the legislation amid dire warnings that Democrats who voted yes risked losing union support.

In the end, however, few lawmakers are believed to have suffered any meaningful repercussions, and none is believed to be in serious political difficulty because of the vote. What was once seen as a potentially decisive campaign issue has largely dissipated while organized labor has focused on other priorities, such as health care and raising the minimum wage.

"We've got lots at stake in this election," said Peggy Taylor, the AFL-CIO's legislative director. "It's not just trade policy."

Corporate-backed groups welcomed the Senate's action as a potential boon for U.S. companies, while administration officials said it could herald a new era in relations with Beijing and encourage greater openness inside China. But some warned that it is now up to U.S. businesses to take advantage of the trade deal and to press China to meet its market-opening commitments.

Despite projections by major corporations of a windfall for American businesses and farmers, it may be some time before the benefits of the trade opening begin to flow in earnest to the United States.

The U.S. trade deficit with China was $36 billion for the first six months of the year, and at this rate it will break last year's record of $68 billion. Administration officials caution that the trade agreement will not have a noticeable effect on the balance of trade, especially as long as American consumers, feeling flush from nearly a decade of economic expansion, continue to buy cheap Chinese imports.

U.S. exports to China, which have been increasing over the past decade and last year totaled $14 billion, could nearly double by 2005 as a result of the market opening, according to some studies.

Administration officials say China is on schedule to become a member of the WTO by the end of the year, although one possible stumbling block is the thorny issue of Taiwan's accompanying accession.

A proposal by Chinese negotiators this summer under which Taiwan would not join as a country but as a "customs territory"--language in keeping with Beijing's insistence that Taiwan is not an independent nation--threatened to undermine an eight-year-old Sino-American agreement governing the terms of Taiwan's entry into the global trading system.

Administration officials say they have told the Chinese government repeatedly that the United States will not accept any changes in the timing or terms of Taiwan's membership.

In a letter to Senate Minority Leader Thomas A. Daschle (D-N.D.) last week, President Clinton said he had reiterated the point at his meeting with Chinese President Jiang Zemin at the United Nations this month and that he is "confident we have a common understanding."

"We have been told repeatedly by the Chinese that they are not going to be a problem," said national security adviser Samuel R. "Sandy" Berger.

China has concluded all but two of the market-access agreements it was required to sign with WTO members before it can join the trade body, and it is expected soon to complete negotiations with the two remaining nations, Mexico and Switzerland. A round of negotiations over the terms of China's accession is underway at WTO headquarters in Geneva.

"I think they will be voted on by the [WTO] body as a whole before the year's end, as will Taiwan," said Charlene Barshefsky, the U.S. trade representative who negotiated last year's market-opening accord. "China's nomination will not get to the floor if Taiwan's nomination is not agreed to follow."

Staff writer Ellen Nakashima contributed to this report.

The 'No' Voters

Following are the 15 senators who voted against extending permanent normal trade relations to China:

Republicans

Bunning, Ky.; Campbell, Colo.; Helms, N.C.; Hutchinson, Ark.; Inhofe, Okla.; Jeffords, Vt.; Smith, N.H.; Specter, Pa.

Democrats

Byrd, W.Va.; Feingold, Wis.; Hollings, S.C.; Mikulski, Md.; Reid, Nev.; Sarbanes, Md.; Wellstone, Minn.

Democrats Not Voting

Akaka, Hawaii; Lieberman, Conn.

CAPTION: The Pact With China (This graphic was not available)