The Gang of Eight does not have 60 votes to get by a Senate filibuster, if you listen to Sen. Marco Rubio (R-Fla.), his colleagues and their aides. That’s hard to fathom, given that there are 55 Democrats, four definite Republicans and certainly some other Republicans who will join the effort. But then the goal in the Senate, really, isn’t to get 60 votes but to get a much higher, overwhelming majority so as to spur the House to act.

Sen. Marco Rubio Sen. Marco Rubio (R-Fla.) (Alex Wong/Getty Images)

A senior Republican aide to a Gang member not authorized to speak on the record told me Tuesday, “There are currently fewer than 60 votes in the Senate. And that’s not just by my count: Sen. Menendez told Univision last week that the bill currently doesn’t have 60 votes, and several red state Democrats told the Wall Street Journal earlier this month that they don’t yet support the bill.” He added, “In order to get the sort of Republican support that we want, we need a border security plan that will give the American people and Republican senators confidence that we won’t have future waves of illegal immigration.”

The uncertainty about the vote count also puts some pressure on those members like Sen. Rand Paul (R-Ky.), who is out in California this week raising money among the Silicon Valley supporters who have pushed for immigration reform. The high-tech donors willl press him to find out if he is really with them on this, or just paying lip service. Others like Sen. John Cornyn (R-Tex.), who have said they’d be open to a bill with greater border security provisions, can now be asked, “Well, what do you want?”

What form would that border security provision take? It’s not clear. I hear only that the Gang of Eight is working on a stronger border plan with Republican Senate offices.

This seems to be a cagey way to proceed. Republican stragglers can show they “got something” more on border security. Rubio, as he said on a Fox New special over the weekend, can acknowledge that the public doesn’t have faith in government, arguing that unless there is something better on border security, the bill won’t pass. Those who have opposed the Gang of Eight plan up until now (in and out of Congress) can be deflected by saying the border security provisions will improve. In essence, the Gang of Eight has some breathing room to build a bigger majority.

What is clear is that Democrats in Congress want a deal badly enough to annoy gay marriage proponents (whose amendment to include gay couples in the definition of marriage was deferred) and to, at least so far, resist other measures that would kill the bill or tamp down GOP support. That gives the Republicans on the Gang of Eight some latitude to round up some more support.

At some point this summer it will be decision time. Do mainstream Republicans get on board? Does the Gang really have a supermajority? Does the president, as anti-immigration reform zealot Sen. Ted Cruz (R-Tex.) says, just want to wreck a deal and blame the Republicans (I guess, Republicans like him)? We’ll find out, but not for a while yet. There is more wooing by the Gang of Eight still to come.