When the Senate takes a vote, there’s a period in which senators stand around the well of the chamber, chatting in groups of two and three, while fellow lawmakers come in and out to cast votes. When that was happening Tuesday on a motion to move to debate on the Gang of Eight comprehensive immigration reform bill, Sen. Kelly Ayotte, who made news Sunday by becoming the first Republican outside the Gang to endorse the bill, was talking with another lawmaker when Sen. Richard Durbin, the number-two Democrat in the Senate and a Gang of Eight member, walked over to her for the briefest of moments. Durbin said just two words: “Thank you.”

And why shouldn’t Durbin be thankful? Ayotte had broken the silence about the bill that had been standard among Republicans not in the Gang. For months, GOP senators have declined to make any commitment to the Gang legislation, choosing instead to make general, talking-point remarks about the need to fix the nation’s “broken” immigration system. On Sunday, Ayotte said straight-out that she will vote for the bill, giving it the beginning of a sense of momentum among Republicans.

In the end, the Senate voted 82-15 to move to debate on the bill. In some circles, that lopsided margin, which included 28 Republican “Aye” votes, was taken as a sign of support, or at least potential support, for the bill. Perhaps, but most Republicans had made the decision that they did not want to stop debate on the bill before it even started; my story last week on the question called the upcoming vote a “done deal.” Most Republicans warned that no one should read too much into their initial vote.

For example, after the vote, Mitch McConnell and John Cornyn, the two highest-ranking Republicans in the Senate, met the press, and Cornyn said this:

Senator McConnell and I both voted to proceed to engage in the immigration debate, the first time since 2007 the Senate’s taken up the immigration issue, and I think there is virtually unanimity that the current immigration system is broken and that action on behalf of Congress needs to take place.

At the same time, Cornyn has written amendment to strengthen the bill’s border security requirements that Senate Majority Leader Harry Reid has called a “poison pill.” In a Facebook posting Tuesday, the same day he voted to move the bill forward, Cornyn wrote:

I…oppose the Gang of 8 bill because it fails to provide a real plan to secure our border and keep our nation safe, offering lofty promises without any guarantees.

I’m voting to move to the bill so that I can offer my RESULTS amendment to toughen the border and national security provisions, putting real teeth in the bill by guaranteeing a plan to secure our porous border.

The bottom line is that if border and national security cannot be guaranteed in this bill, I cannot and will not support it.

So don’t read too much into the first vote on the Gang of Eight bill. Yes, with 54 Democrats and five Republicans supporting it so far, its prospects for final Senate passage are very, very strong. But how many GOP lawmakers will end up voting for it is still an open question.

By the way, there were two votes on the bill Tuesday, one to invoke cloture and one to move ahead with debate. Both passed by similar margins. The only senator to miss both votes was Gang member and longtime immigration reform advocate John McCain.