The congressional battle over immigration reform began in earnest yesterday as the Senate Judiciary Committee jumped into the amendment process. The Senators started on the border security section of the legislation and Republicans spent much of the eight-hour session calling for significantly more border control. Though at the end of the day, the legislation moved only slightly to the right, the minority party's zeal for more enforcement appeared nearly unlimited. On Tuesday, Senators on the Committee filed over 300 amendments to the legislation. Yesterday, as they began the voting process, the 18 members got through 32 of the proposed changes. Several amendments passed to increase the border buildup in the already border-heavy bill. The committee approved an amendment from Sen. Chuck Grassley, R-Iowa, to require border patrol to stop and detain 90 percent of border crossers on the entire border. As the bill was originally written, that "effective control" provision applied only to areas with historically high rates of crossing. The Senators also agreed on an amendment that will require the Department of Homeland Security to report back to the Judiciary Committee. The Democrat controlled committee rejected several more amendments from Grassley and other members that would have strengthened so-called border triggers and threatened the path to citizenship entirely. Even with the additional amendments, some Republicans said they would simply not support the legislation. "The committee has voted down every serious border security amendment today," said Sen. Ted Cruz, a Texas Republican. "If it doesn't have real border security, it will not pass." The comments from Cruz beg the question: What is enough enforcement? And the tone many Republicans set suggests that for them there's no limit. In the Senate, those Republican demands may not prevail, but in the Republican controlled House, which has yet to begin deliberations on reform, these sentiments will be powerful obstacles. Meanwhile, the willingness of Democrats and members of the bi-partisan Gang of Eight Senators who wrote the bill to agree yesterday to several of the border enforcement amendments has some asking how far they'll be willing to move to the right as the rest of the amendments come to vote in the next several weeks. The next section of the bill, which the Senators are expected to take up on Tuesday, contains the 10-year path to citizenship. While Democrats and the two Republican Gang of Eight members on the committee will reject proposals from Cruz and others that would gut the path to citizenship, there are many smaller amendments that could dramatically limit the promise of the reform bill. An amendment filed Tuesday by Sen. Jeff Sessions, a veteran and vocal opponent of immigration reform, would remove from the bill a provision allowing deported parents, spouses and children of U.S. citizens to apply to come back to the U.S. That provision, which could help tens of thousands of families reunify, was seen as a major victory by immigrant rights advocates who point to the crippling effect of deportations on families. It's not clear though on which side of the Gang of Eight and Democrats threshold for compromise that provision will fall. In a similar way, two amendments from Committee Chairman Sen. Patrick Leahy, D-Vt., would add immigration rights for same-sex couples. The original legislation excludes LGBT rights. Tens of thousands of gay U.S. citizens are now prohibited from petitioning for green cards for their non-citizen partners because of federal laws. The Leahy amendments aim to fix this discriminatory legal arrangement. But Gang of Eight member Sen. Chuck Schumer, D-N.Y., has yet to say how he'll vote on the measure, which Republicans broadly oppose. Republicans were not the only ones to propose additional enforcement yesterday. The committee passed an amendment from California Democrat Sen. Diane Feinstein's that could increase funding to localities to prosecute non-citizens in the criminal justice system. Ultimately, it appears the comprehensive immigration reform bill will move to the right as it is amended. The question though is how far can it move in that direction before it's too exclusionary for some Democrats and immigration reform advocates to accept.