WASHINGTON -- Democrat John Kerry, whose nominating convention highlighted his war service and focused on national security, has narrowed the gap on President Bush's strong suit of protecting the country, according to an Associated Press poll that shows the race remains tight. Flanked by his Vietnam crewmates, Kerry delivered an acceptance speech last week laden with references to patriotism, his decorated military record and his qualifications for commander in chief -- a theme underscored by speaker after speaker over the four-day gathering. The images and rhetoric registered with a number of voters. In the AP survey conducted Tuesday through Thursday,...