John McCain at campaign rally after winning Republican party primary in New Hampshire, 8 Jan. 2008

The birth more than seven decades ago of Senator John McCain in the Panama Canal Zone has been the center of recent debate on what the U.S. Constitution means when it says a person must be a "natural born citizen" to be eligible for the presidency.

Legal experts, lawmakers and political pundits have taken up the topic recently since the constitution does not define the phrase.

The U.S. Senate made its position known on the matter, unanimously passing a nonbinding resolution on April 30 that declared that the veteran Arizona lawmaker, war hero and Republican presidential nominee-in-waiting is eligible for the presidency.

Supporters of the resolution included McCain's Democratic rivals, Senators Barack Obama and Hillary Clinton.

McCain was born August 29, 1936 in the Panama Canal Zone, which was under U.S. jurisdiction at the time.

Besides being a natural born citizen, other requirements for the presidency include that a person must be at least 35 years old and have been a resident within the United States for 14 years.

Some information for this report was provided by AFP and AP.