Democrat John Kerry (search) is pressuring President Bush (search) on his strongest issue, national defense, but the incumbent retains an advantage there, an Associated Press poll found.

The Democratic National Convention (search) in late July focused heavily on Kerry's war service and on national security, a strategy that appears to be paying dividends for the White House challenger.

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.

In the AP survey conducted Tuesday through Thursday, 43 percent said Kerry would do a better job of protecting the country -- a gain of 8 percentage points from a similar survey in March.

Republican Bush still has the advantage on the issue, with 52 percent saying he would do better in protecting the nation. But Bush's percentage on the issue has dropped 6 percentage points since March, according to the poll conducted for the AP by Ipsos-Public Affairs, and the latest survey was taken as he faced questions about dated intelligence for increased terror alerts.

Kerry improved his standing on the issue with a demographic group that tends to lean Republican: men under age 45.

Edison Montgomery, a 59-year-old Democrat from Lancaster, Ohio, said that after watching the convention he has grown more comfortable with Kerry -- especially on whether he is capable of protecting the nation.

"He seems like he's got a good head on his shoulders," Montgomery said.

Despite the gains for the Democratic challenger, Bush and Kerry remained essentially tied in the presidential race -- a position they have been in for months.

In a three-way matchup, Kerry and running mate John Edwards have the backing of 48 percent, Bush and Vice President Dick Cheney 45 percent and independent Ralph Nader and running mate Peter Camejo 3 percent among registered voters.

The poll of 798 registered voters had a margin of error of 3.5 percentage points.

In July, Bush had a slight lead over Kerry -- 49 percent to 45 percent -- with 3 percent backing Nader.

Although Bush's ratings have dipped in other areas, including his stewardship of the war in Iraq and his handling of the economy, 51 percent still approve of his handling of the war on terrorism to 48 percent who disapprove in the AP poll.

"I don't think Kerry's ready to be president," said Laura Weber, a 37-year-old Republican from Pierre, S.D. "Bush would be more decisive."

The economy has been improving in fits and starts but continues to be a troublesome issue for Bush. Fewer than half polled -- 46 percent -- said they approve of the Republican's handling of the economy, about the same percentage as in July.

Kerry held a clear advantage over Bush on the question of who would do better at creating jobs, with 55 percent naming Kerry and 39 percent saying the president -- a number essentially unchanged from March.

The job numbers released Friday are likely to reinforce that perception.

New figures on job growth in July were far below analysts' predictions, with only 32,000 jobs being added -- a potentially troubling sign that the rough patch the economy hit in June was not an isolated problem despite 11 consecutive months of jobs growth. Analysts had expected the economy to add anywhere from 215,000 to 247,000 jobs in July.

All together, 1.1 million jobs have been lost since Bush took office in January 2001.

"We have a long way to go on jobs," said Cara Easterly, a 37-year-old Democrat from the Seattle area. "I don't think Bush is focused on the problem. He's more focused on what's going on outside the country."

Strong support for Bush and Kerry now is about even, with 32 percent saying they are backers of the Republican and 31 percent saying their candidate is Kerry. In July, Bush was slightly ahead of Kerry in intensity of support.

"I think President Bush has done an excellent job," said Linda Roberts, a conservative Republican from Liberal, Kan. "He's a Christian. I don't believe there's any reason to kill babies by abortion. I don't believe in gay marriage. I believe he is for equal rights, but also for God's rights."