The lawmakers themselves discussed a small number in meetings held either in the office of Sen. Chuck Schumer, D-N.Y., or John McCain, R-Ariz.
Even though immigration legislation is a top priority for President Barack Obama, the White House was held at arms' length. Administration officials were consulted about the feasibility of quickly establishing a nationwide biometric system to track immigrants, for example, but were not invited to the meetings.
It was only by accident that the public might have learned of the gang's power.
Speaking into a microphone that he evidently did not realize would pick up his voice, Schumer asked an aide during one vote, "Do our Republicans have a pass on this one?"
In fact, for days, the two GOP Gang of Eight members on the committee, Sens. Jeff Flake of Arizona and Lindsey Graham of South Carolina, wound up opposing changes they might otherwise have supported — far more often than was the case with the Democrats, Schumer and Sen. Dick Durbin of Illinois.
Among them were numerous attempts by other Republicans to toughen border security requirements before legalization can begin or to otherwise make provisional legal status harder to obtain.
Still other proposals were reshaped to meet the conditions of the Gang of Eight, including one by Sen. Patrick Leahy of Vermont and John Cornyn of Texas, one the Democratic committee chairman, the other the Senate's second-ranking Republican.
They wanted to change a provision providing $1.5 billion to deploy "additional fencing in high-risk border sectors," proposing instead that the money go to "fencing, infrastructure and technology." Officials said that ran afoul of the wishes of Sen. Marco Rubio, a member of the Gang of Eight, who had made construction of the fence a priority.
In the end, a compromise emerged, with $1 billion to be spent exclusively on fencing and $500 million available for that purpose or other infrastructure or technology.