Republican presidential contender John McCain is headed for Colombia Tuesday as part of an effort to show his support for free trade and his expertise in foreign policy.  McCain's Democratic opponent, Senator Barack Obama, spoke about faith Tuesday as he reached out to a group of voters generally more supportive of Republican presidential candidates.  VOA National correspondent Jim Malone reports from Washington.

Senator McCain's trip includes stops in Colombia and Mexico.

McCain is expected to highlight Colombian efforts against drug trafficking and his support for a U.S.-Colombian free trade deal that has stalled in the U.S. Congress.

McCain has criticized Senator Obama for wanting to re-negotiate the North American Free Trade Agreement with Canada and Mexico.

On Tuesday, McCain vowed to stay on the offensive against violent crime in the United States and promised to appoint federal judges who have what he called a proven commitment to judicial restraint.

"They will be the kind of judges who believe in giving everyone in a criminal court their due, justice for the guilty and the innocent, compassion for the victims, and respect for the men and women of law enforcement," he said.

For his part, Senator Obama was in Ohio Tuesday, reaching out to religious voters, a group that has been hesitant to support recent Democratic presidential candidates.

Obama promised to expand President Bush's program to give federal support to faith-based charities to battle poverty, a program that some Democrats oppose.

"We know that faith and values can be a source of strength in our own lives," he said.  "That is what it has meant to me, and that is what it has been to so many Americans."

Obama vowed to uphold the traditional separation between church and state in carrying out the programs.

Obama also remains on the defensive over the comments from one of his supporters, retired U.S. Army General Wesley Clark.

Clark told the CBS program Face the Nation Sunday that Senator McCain's military experience in Vietnam did not necessarily qualify him for the White House.

"Well, I do not think that riding in a fighter plane and getting shot down is a qualification to be president," he said.

McCain was shot down during the Vietnam War and spent 5.5 years as a prisoner of war.

Clark's comments drew fire from McCain supporters and even some Democrats, and Obama was asked about it at a news conference Tuesday in Ohio.

"Senator McCain's service is heroic and he deserves out respect for that," he said.  "Now, I have differences with him on policy."

Obama's focus on faith came one day after he talked about patriotism, part of a series of speeches leading up to the U.S. Independence Day holiday on July 4.