A new public opinion poll shows President Bush and Democratic challenger John Kerry tied at 49 percent among likely voters less than a month before election day.
The poll by the Gallup organization was the latest to show Senator Kerry closing the gap on the Republican president after their debate last week.
Respondents felt Mr. Kerry would do a better job handling the economy, but gave Mr. Bush the advantage on Iraq and the war on terror.
Monday, Senator Kerry campaigned in the northern state of New Hampshire, where he promoted his plan to expand federal stem cell research.
Meanwhile, President Bush signed a new tax reduction bill during a campaign stop in the midwestern state of Iowa.
The candidates' vice-presidential running mates, Republican Dick Cheney and Democrat John Edwards, are preparing for a televised debate to be held on Tuesday.