Tune in to VOA News Now at 0045 UTC Saturday for our live radio and television coverage of the third presidential debate of 2004.

The next big moment in the U.S. presidential campaign comes Friday in St. Louis, Missouri, when President George Bush and Senator John Kerry hold their second of three debates.

The format for the Friday debate will be different from the other debates where a single moderator asks all the questions.

In St. Louis, voters will get to quiz the candidates on a range of foreign and domestic policy issues. The voters taking part are selected by the Gallup Polling organization.

Even most Republicans acknowledge that Senator Kerry turned in a strong performance in last week's first debate and they are expecting a more aggressive President Bush on Friday.

"I think for Bush, the conversation has to be focused on Kerry," says John White, who lectures on U.S. politics at Catholic University in Washington. "That is, you may not have liked the last four years, fellow Americans, but do you really want to entrust the security of the United States to this man, John Kerry?"

Democrats are hoping that Senator Kerry can build on his momentum from the first debate. Public opinion polls indicate the Massachusetts Senator got a boost from that debate by putting the president on the defensive and laying out in more detail what he would do about Iraq if elected.

"We are, I think, starting to move back towards a referendum on the president because we had one debate, which basically got John Kerry into the game," says Norman Ornstein, an expert on the presidency at the American Enterprise Institute in Washington. "It began to move him to a point where he could clear the bar and be seen by voters who are uneasy about the status quo as a [viable alternative]."

But even many Democrats concede that the Bush campaign has done an effective job for the past several weeks of focusing public attention on John Kerry's record in the Senate and his changing positions on Iraq.

"An election with an incumbent running for re-election is always a referendum on the incumbent," says William Schneider, a veteran political analyst at the American Enterprise Institute. This election campaign so far looks a little bit different. It looks much more like a referendum on John Kerry."

The latest public opinion polls suggest the race remains very close and that Iraq continues to be a major concern for most voters.

"The number of people citing Iraq as the most important problem facing the country has gone up in nearly all recent polls," says Karlyn Bowman, who monitors public opinion for the American Enterprise Institute. "The verdict on the president's handling of the situation there is decidedly negative. If there is good news for the president on Iraq, it is that the American people still do not think that Kerry could do a better job there."

Senator Kerry spent time in Colorado preparing for Friday's debate while President Bush held a rally in Wisconsin.

Historically, presidential debates have had an impact on elections, especially when the race is close.

The third and final presidential debate will be held next Wednesday in Arizona.