Sen. John McCain, R-AZ, just popped out of a closed session of the Senate Armed Services Committee to reveal that the he had just scored a significant victory on his border security amendment that would mandate the President send 6,000 National Guardsmen to the US-Mexico border.

"Getting it through the...committee is very important as part of the Defense Authorzation bill...Over 80% of the American people support sending the Guard to the border and sooner or later Democrats will react to public opinion," McCain told Fox.

The authorization bill is widely considered to be a must-pass piece of legislation. The bill sets the spending blueprint for defense policy that is eventually funded through the annual appropriations process.

Anything attached to this bill stands a better chance of passing in the end, though it is certainly possible that the measure could eventually be dropped in conference with the House.

But McCain, who is in the middle of a rough GOP primary fight with an anti-immigration opponent, told Fox, "If you believe in representative government, when 80% of the American people support something, then sooner or later, even though there's a huge disconnect between Washington and the people, the Democrats will have to listen."

Democrats defeated an earlier attempt Thursday by McCain to add the Guard mandate to an emergency spending bill saying that not only was the effort "overmagnified" but it ignored the need for a comprehensive fix for the U.S. immigration system.

McCain strongly disagreed, saying, "The people in Arizona are not living a secure life. Every government has the obligation to secure its citizens."