Republican Sen. John McCain fought for the U.S. Navy in the Vietnam War.

He was taken prisoner and held captive for more than five years during his deployment.

McCain was a proponent of using military force in Iraq.

He supported the recent troop surge and says even more American troops are needed in Iraq to speed up training for Iraqi security forces.

If elected, McCain says he'll sign the so-called "fair tax" into law if it comes to his desk - replacing the income tax with a higher sales tax.

He didn't sign a pledge promising not to raise taxes.

McCain co-sponsored a bipartisan immigration reform bill, backed by the Bush administration, that would have improved law enforcement and technology along the borders.

It also would have created a legal path to citizenship for some illegal immigrants.

McCain supports a guest worker program, and he voted to authorize construction of a 700-mile fence along the U.S.-Mexican border.