The political gap was particularly large in terms of views on free trade with Mexico. Contrary to a positive view of free trade with Canada, which 79% of Americans called fair trade partners, only 47% of Americans thought that Mexico practiced fair trade. The gap between Democrats and Republicans has widened: 60% of Democrats thought Mexico was fair trade, while only 28% of Republicans did. That was the highest number of Democrats and the lowest figure ever recorded by Republicans in the Chicago Council survey. Republicans had more negative views on Canada than fair trade partners and Democrats.  Before sending it to the U.S. Senate, Clinton added two subsidiary agreements, the North American Agreement on Labor Cooperation (NAALC) and the North American Agreement on Environmental Cooperation (NAAEC) to protect workers and the environment, as well as to allay the concerns of many members of the House of Representatives. The United States has required its partners to comply with similar environmental practices and regulations. [Citation required] After much attention and discussion, the U.S. House of Representatives passed the North American Free Trade Agreement Implementation Act on November 17, 1993. Supporters of the deal included 132 Republicans and 102 Democrats. The legislation passed the Senate on November 20, 1993, 61-38.
 The Supporters of the Senate were 34 Republicans and 27 Democrats. Republican Congressman David Dreier of California, a staunch supporter of NAFTA since the Reagan administration, has played a leading role in mobilizing support for the agreement among Republicans in Congress and across the country.   A “subsidiary agreement” reached in August 1993 on the application of existing domestic labour law, the North American Convention on Labour Cooperation (NAALC) , was severely restricted. With regard to health and safety standards and child labour law, it excluded collective bargaining issues, and its “control teeth” were only accessible at the end of a “long and painful” dispute.  The obligations to enforce existing labour law have also raised questions of democratic practice.  The Canadian anti-NAFTA coalition Pro-Canada Network suggested that guarantees of minimum standards in the absence of “extensive democratic reforms in the [Mexican] courts, unions and government” would be of no use.  However, subsequent evaluations indicated that NAALC`s principles and complaint mechanisms “created a new space for princes to form coalitions and take concrete steps to articulate the challenges of the status quo and promote the interests of workers.”  Canada experienced strong growth in cross-border investment in the NAFTA era: since 1993, investment in the United States and Mexico has tripled in Canada. U.S.
investment, which accounts for more than half of Canada`s fleet, has grown from [PDF] $70 billion in 1993 to more than $368 billion in 2013. Many analysts explain these differences in results by the fact that the Mexican economy is “two-speed”, where NAFTA has led the growth of foreign investment, high-tech production and wage growth in the industrial north, while the south, largely agricultural, has remained disconnected from this new economy.