On June 27, 2013, the U.S. Senate approved S.744, the “Border Security, Economic Opportunity, and Modernization Act,” in a historic 68-to-32 vote that will now send the comprehensive reform bill to the U.S. House of Representatives, where it is expected to face significant opposition from the Republican majority. The legislation is a product of record bipartisan cooperation among lawmakers, business groups, labor unions, agricultural interests, and immigration advocates, who painstakingly negotiated compromises resulting in a broad architecture for reform – including a path to citizenship for 11 million undocumented immigrants, a new temporary worker program, increased visa numbers for skilled foreign workers, and a nationwide employment eligibility verification system.

Importantly, Republican support for S. 744 was greatly bolstered by the June 26, 2013 passage of a border security amendment that will devote approximately $40 billion dollars to add 20,000 additional Border Patrol agents and 700 miles of fencing along the U.S. border with Mexico over the next 10 years.

The bill had previously withstood committee “mark-up” in a process spanning five days and over 300 amendments, including a dramatic decision to withdraw a measure that would allow the same-sex spouses of U.S. citizens to obtain green cards in the same manner as heterosexual couples.  This highly contested amendment is now expected to become moot after the U.S. Supreme Court invalidated the Defense of Marriage Act earlier this week.

Despite a noteworthy showing in the U.S. Senate, the bill is expected to face substantial challenges in the U.S. House of Representatives, where Republican leaders have advocated issue-specific changes to the nation’s broken immigration system in lieu of enacting comprehensive reform. According to some immigration experts, a likely and desirable outcome as S. 744 proceeds to the second chamber is that it will enter the “conference” process and ultimately emerge as a version both parties can agree to enact into law.