WASHINGTON -- Sens. John McCain (R-Ariz.) and Lindsey Graham (R-S.C.) said on Tuesday they came out of a meeting with President Barack Obama more confident that he understands their argument that border security must be given prominent weight in plans for comprehensive immigration reform.

"It was one of the best meetings I've ever had with the president," Graham told reporters.

"He understands we need border security that we can afford, and Senator McCain made a strong point about the border," he added later. "The president understands the working components of it, so I was, quite frankly, encouraged."

McCain wouldn't comment on what he told the president, but also said Obama seemed to be listening to his concerns about the southwest border.

"I am more confident after our conversation today," he told reporters.

How immigration reform legislation will address border enforcement -- and more importantly, whether green cards should be tied to border metrics -- is a potential sticking point as talks move forward. Both the White House and the Senate "gang of eight," of which Graham and McCain are members, have called for increased border enforcement efforts, but they differ slightly on certain issues. The Republican senators' confidence indicates progress toward an agreement that would both pass Congress and meet Democrats' number one goal: a pathway to citizenship for undocumented immigrants already in the United States.

The meeting was planned last week, when Obama personally telephoned McCain, Graham and Sen. Marco Rubio (R-Fla.) to discuss it. McCain said Tuesday it was his first meeting with Obama on immigration since early in the president's first term.

The proposal by the "gang of eight" -- which includes Republican Sens. McCain, Rubio, Graham and Jeff Flake (R-Ariz.) and Democratic Sens. Chuck Schumer (D-N.Y.), Dick Durbin (D-Ill.), Bob Menendez (D-N.J.) and Michael Bennet (D-Colo.) -- goes a step further than Obama's plan by tying green cards for undocumented immigrants to border metrics. Their framework, unveiled Jan. 28, would create a pathway to citizenship that would start with provisional status, then allow for green cards once the border was considered adequately secure.

It's in part a political measure, as many members are wary of allowing undocumented immigrants to become citizens if it could lead to a future swell of unauthorized immigration. If they can show their bill wouldn't allow legalization to move more quickly than increases in enforcement, the "gang of eight" hopes they can make Republicans more amenable to it.

The Obama administration has neither endorsed the idea nor rejected it outright, but has cautioned against holding all of immigration reform hostage to border security. Draft legislation from the White House does not include a trigger for its pathway to citizenship.

Neither Graham nor McCain would say if the president had indicated whether he would support their plan. But McCain said Obama "understands the parameters" of the group's plan and seems to genuinely want to find passable legislation.

"I believe that the president is very committed to comprehensive immigration reform," he said. "Does that mean he's committed to anything we do? No, he has his positions on the issue as well. But I believe he is sincerely desirous of comprehensive immigration reform."

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  • "Gang Of Eight"

    A <a href="http://www.huffingtonpost.com/2013/01/28/immigration-reform-framework_n_2566494.html?1359387491">bipartisan group of senators</a> have come together to address the issue of immigration reform. The group consists of four members of each party -- Democratic Sens. Chuck Schumer of New York, Dick Durbin of Illinois, Bob Menendez of New Jersey and Michael Bennet of Colorado, plus Republican Sens. Lindsey Graham of South Carolina, Marco Rubio of Florida, John McCain of Arizona and Jeff Flake of Arizona. Their framework was announced Monday.

  • Pathway To Citizenship

    A <a href="http://www.docstoc.com/docs/142894316/Bipartisan-immigration-plan">"tough but fair" </a> road to citizenship is the main tenet of the bipartisan immigrant plan. Sen. Marco Rubio (R-Fla.) is the most significant supporter of this idea, giving hope to those who doubt Republicans will support the plan.

  • The New Process

    The new process of obtaining citizenship would be just that -- a process. Probationary citizens would be required to pass an additional background check, learn English, pay taxes and show that they have a history of employment to apply for permanent residence and a green card. Undocumented immigrants will receive green cards after all probationary citizens have been processed, ensuring that documented immigrants are addressed first. Separate processes would be designed for young undocumented immigrants who came to the US as children and agricultural workers.

  • Enforcement, Then Green Cards

    The first goal, before any green cards are handed out, is to "demonstrate our commitment to securing our borders and combating visa overstays," the senators say in their framework.

  • Enhance Border Security And Drones

    Emphasizing enforcement measures, the framework calls for increased boarder control, including more border agents and aerial surveillance and drones. A new system would be added to ensure visa stays are being adhered to, along with a commission of border lawmakers to aid legislation.

  • Increase Employment Verification

    The senators have proposed to create an "effective employment verification system" that would help prevent identity theft while allowing employers to feel secure in hiring documented immigrants.

  • No Benefits For Probationary Immigrants

    Immigrants who are in the probationary category would not be eligible for federal benefits in the senators' framework. This addresses the concern that public benefits, particularly health-related ones, are being spent on undocumented immigrants.

  • An Easier Path For 'The Best And Brightest'

    The framework recognizes that a different sort of process would be needed for "the best and brightest," including highly-skilled workers and those with higher education. This has been previously addressed in the <a href="http://www.huffingtonpost.com/2012/11/28/stem-act-white-house-immigration_n_2207279.html">STEM Act </a> which was ultimately vetoed by the White House.