Sen. Marco Rubio (R-Fla.) (Joe Raedle/Getty Images Sen. Marco Rubio (R-Fla.) (Joe Raedle/Getty Images

Immigration-reform legislation continues to be shaped through a series of Senate Judiciary Committee amendments. Today, Sen. Marco Rubio (R-Fla.) sent out an email explaining that an amendment by Sen. Jeff Sessions (R-Ala.) was crushed:

The amendment would have limited the number of people who could immigrate to the United States, weakening future legal immigration. Specifically, the amendment would explicitly limit legal immigration to 1.2 million people per year, eliminating important aspects of the merit-based system and stripping the improvements made to the employment-based visa system. In essence, the amendment would have changed the bill to repeat many of the mistakes of the failed 2007 immigration bill. Republican Sens. John Cornyn and Ted Cruz of Texas, Charles E. Grassley of Iowa and Mike Lee of Utah joined with the rest of the Judiciary Committee to oppose the amendment as offered by Sessions.

In addition, Rubio’s office notes that an amendment from Sen. Orrin Hatch (R-Utah) is under consideration. It would address concerns that the so-called STEM (science, technology, engineering, and mathematics) provisions in the proposed bill are not sufficient. Hatch’s amendment would allow each state “to determine how best to spend the new STEM education funds.”

These developments are important in two respects. First, as with the flawed Heritage study, it is important to distinguish between those who have concerns about the exact type of immigration reform we pursue and those who would never be happy because they don’t like immigration, period. (Sessions’ office last week sent out an email praising the widely denounced Heritage study). Second, even Cruz, who wants no part of immigration reform that involves the essential element of legalization (in other words, any passable bill), didn’t want to line up with Sessions. Perhaps the Heritage incident sensitized lawmakers to the perils of ridiculing immigrants and perpetuating nonsensical theories that we don’t need immigration or that it shrinks the economy.

Just how fringe is the opposition to immigration reform getting? Buzzfeed reports:

Sen. Lindsey Graham is the first target of a new broadcast ad campaign from an anti-immigration reform group with reported ties to the white nationalist movement.

The minute-long radio ad campaign by ProEnglish, comes at a particularly bad time for opponents of comprehensive reform: last week the Heritage Foundation was forced to sack a researcher for his racially tinged comments about Latinos and there are growing questions about the anti-reform movement’s connections to radical population growth groups.

Anti-immigration reform advocates who don’t share these view would be smart to denounce and distance themselves from such characters.

Senators who can be expected to get on board eventually are having success passing their amendments. Those who will never be satisfied are being marginalized. This is how the legislative process generally works — grow support and minimize opposition.

Paying too much attention to squawking from anti-reform groups and immigration exclusionists can be misleading as an indication of the Gang of Eight’s chance of passing a reform bill. With each amendment, the bill is getting more conservative — and more likely to pass the Senate.