Senate Republicans looking for ways to support a series of changes in the nation's immigration laws are hoping to unveil as early as Wednesday several possible amendments regarding border security, benefits for illegal immigrants and how employers would track a job applicant's immigration status.

Sen. Bob Corker (R-Tenn.). (AP)

The senators and their aides caution that plans remain fluid, but that they hope to have a plan in place by the end of Wednesday to present to bipartisan sponsors of the immigration bill and Senate Democrats.

If the proposals are accepted by the bill's sponsors and eventually added to the bill, they could help ensure as many as 70 votes in favor of the immigration bill, an impressive bipartisan margin that supporters believe would compel the Republican-controlled House to consider similar legislation.

The Republican senators hoping to introduce amendments are working in close consultation with members of the bipartisan "Gang of Eight," who wrote the bill and are leading delicate negotiations. These include several senators from Midwestern and southern states, who have long sought ways to strike bold, bipartisan agreements on immigration and budget and fiscal policy.

Sen. John Hoeven (R-N.D.) said he is working on a border security proposal that would insert plans already drafted by the U.S. Customs and Border Protection and Immigration and Customs Enforcement into the immigration bill. The plan drafted by the immigration agencies includes specific goals for different sectors of the U.S.-Mexico border and would require the Department of Homeland Security to meet certain requirements before immigrants begin applying for legal status. Throughout the immigration talks, Republican senators have insisted on implementing various "triggers" that would need to be met before eligible immigrants could begin the legalization process.

"What we’re shooting for is something that will have broad public support and should engender strong bipartisan support in the Senate," Hoeven said in an interview. "That’s going to be important not only in the Senate, but also in terms of what the House does and ultimately getting a bill."

Other proposals in the mix according to Hoeven are ones by Sen. Rob Portman (R-Ohio) to make changes to DHS's E-Verify system used to check the immigration status of job applicants; ideas from Sen. Saxby Chambliss (R-Ga.) regarding agricultural workers; and some ideas from Susan Collins (R-Maine).

Sen. Bob Corker (R-Tenn.), who is also eager to support the immigration bill, told reporters Tuesday that he is having "a lot of healthy conversations" about packaging together several proposals to address the specific concerns of like-minded colleagues.

“I think a good solution is to try to package together two or three or four amendments, I don’t think there’s one amendment that sort of gets at all the issues. But I think there’s a real desire to see where we might go with that," he said.

Aides later said that Corker is reviewing several ideas regarding border security, immigration visas and other issues.

Discussions among Republicans began in recent days as they realized that an aggressive border security proposal introduced last week by Sen. John Cornyn (R-Tex.) lacks sufficient support to be adopted as part of the bill. The Gang of Eight and Senate Democrats oppose Cornyn's plan, saying that its strict border security requirements would make it virtually impossible for any of the estimated 11 million illegal immigrants in the U.S. to eventually begin applying for permanent legal status.

Eager to find some kind of solution that would toughen border security but stop short of Cornyn's plan, Republicans kept talking -- and the first signs of serious progress came Tuesday afternoon as senators voted on the first four amendments to the massive proposal.

From the gallery above the chamber, reporters watched as Republican members of the gang -- Sens. John McCain (Ariz.), Lindsey O. Graham (S.C.), Marco Rubio (Fla.) and Jeff Flake (Ariz.) -- spent several minutes huddled with Corker, Hoeven, Portman, Cornyn and others.

When the talks in the far back corner of the room broke up, six of the eight gang members gathered in the middle of the room by the desk of Senate Minority Leader Mitch McConnell (R-Ky.). There, McCain, Graham, Rubio and Flake conferred with Sens. Charles E. Schumer (D-N.Y.) and Robert Menendez (D-N.J.).

"Right now, good," Schumer could be heard telling the gang as they dispersed across the chamber.

McCain, Graham, Rubio and Flake returned to their corner to speak with Cornyn, while Schumer could be seen whispering to Senate Majority Leader Harry M. Reid (D-Nev.) about the talks. McCain later walked over to share more details.

McCain was especially energized throughout the vote and at one point even tugged on the lapels of Sen. John Thune (R-S.D.) as he was making a point. Sadly for reporters watching, the contents of their discussion were out of earshot.

When the voting ended, members of the Gang of Eight hinted they were on the verge of an agreement that would score enough GOP support to move the immigration bill toward final passage.

"The fact that people want to find new ways to secure the border is encouraging," said Graham, who said he was awaiting further details before determining whether the gang could support the proposals.

Schumer was also in a wait-and-see mood: “The more Republicans we can bring without sacrificing our basic principles, the better. And that’s what we’re trying to do: Not sacrifice our principles, but get more Republicans on board. We’re working very hard, almost 24/7 to try and see what happens.”

By the end of the day Wednesday, McCain told reporters, "you will know whether this thing is coming together or is splitting apart.”

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