Bush, the Republican presidential candidate, led Kerry 52 percent to 44 percent among likely voters, and among registered voters, 49 percent to 46 percent, according a USA Today/CNN/Galluppoll conducted last Thursday through Saturday.

However, even Bush's lead among likely voters was on the cusp of the poll's margin of error at plus or minus four percentage points.

Bush led Kerry on Iraq, terrorism and tax, while Kerry was ahead of Bush on such domestic issues as Medicare, budget, social security and health care. The two were virtually even on economy and education, with Bush trailing slightly by one or two percentage points.

With 15 days to go, strategies in both camps were making final calculations about where the candidates should stop, what they should say and which TV ads should air, as every step and misstep could affect their race to finish.

Kerry was emphasizing domestic issues and targeting swing voters, while Bush was hammering the war on terrorism - his strongest issue - and aiming his message at reliably Republican voters, and both were guarding against an offhand remark that could create an unwanted controversy, a USA Today report said.