As fans of an immigration overhaul breathlessly follow the Senate’s “gang of eight,” it’s important to understand how crucial a robust regular-order process is to keeping Sen. Marco Rubio on board.

The Floridian, perhaps more than any other Republican, has the ability to deliver conservative support for a comprehensive immigration overhaul, or at least to prevent a fatal backlash, including among House members. But assuming that Rubio remains happy with the philosophical principles undergirding a deal that is still being worked out by the bipartisan gang of eight, the process by which actual legislation is moved through the Senate is just as important to maintaining the Florida Republican’s backing.

“We want public hearings, a committee markup and an amendment process on the floor,” Rubio spokesman Alex Conant told CQ Roll Call on Monday. “We need to get buy-in from [everyone.] We want people to understand what’s in the bill and what’s not in the bill.”

Rubio’s letter

But Rubio advisers made clear that he views a lengthy, traditional process that includes hearings, a healthy committee markup and an open floor debate during which senators can offer amendments as key to his ability to build and maintain conservative support for a comprehensive immigration rewrite. Rubio does not have a specific timetable in mind. But anything viewed as “rushed” would violate promises he made to grass-roots conservatives and could cost his support, even if he is OK with the bill in principle.

President Barack Obama has warned that if Congress doesn’t act quickly, he’ll introduce his own immigration bill and exert pressure on lawmakers to approve an overhaul. And critics of Rubio’s deliberate approach will probably warn that slow-walking legislation will provide opponents time to assemble sufficient public opposition to sink the bill.

But Rubio, who remains as supportive of an overhaul as he was when the gang of eight began negotiating, has calculated the exact opposite.

He ascribes Congress’ past failures to approve immigration policy changes to a rushed legislative process. He believes that moving too fast on an issue as sensitive and complicated as immigration generates voter suspicion and makes it more difficult for broad, bipartisan support to build behind the effort. A bill negotiated in a backroom, in his view, could lead to surprises that scare members away from supporting the bill and result in fewer lawmakers taking ownership of the legislation.

But Rubio also is keenly aware of important political realities as they relate to the conservative base of the GOP and the stature he commands within that movement.

During the 112th Congress, most major legislation was decided in closed-door negotiations that included only a handful of members, after which a bill was presented to rank-and-file lawmakers as a take-it-or-leave it proposition. This strategy caused frustration, particularly among House Republicans, and was partly responsible for Speaker John A. Boehner’s decision this year to renew his commitment to running legislation through “regular order.”

Rubio understands this frustration, which he has felt in the Senate as well. That’s why, during his media blitz on conservative talk radio back in January, he vowed to Rush Limbaugh and other influential hosts that the legislative process for an immigration overhaul would be transparent and deliberate, and that he would not be a party to jamming a bill through Congress.

Regular order would also allow Rubio the time he needs to show conservatives that he’s fighting for the principles that are important to them, regardless of the final makeup of the legislation and whether it passes.

In the end, Rubio is telling his colleagues, the perception of the legislative process here is as politically important to the success of the legislation as what’s in the bill.