WASHINGTON – Candidates across the country enter the final week of the campaign with control of Congress very much at stake and both parties determined to influence the few remaining undecided voters with an onslaught of negative messages.

For Republicans, whose grip on the House and the Senate is threatened, the attack will be waged primarily on issues of security and character. By one estimate, more than 90 percent of the television time bought by the Republican National Committee in the closing days has been for negative ads.

For Democrats, who see this as their best chance to regain power since the party lost control of Congress in 1994, the negative surge will come amid questions about President Bush's stewardship of the Iraq war and the honesty of congressional Republicans.

“The Republicans will continue to try to make sure that the voters know that the Democrats are evil incarnate,” said Jim Duffy, a Democratic veteran of several campaigns. “And the Democrats will keep pushing back on the war and the dislike of the president by a majority of the electorate. The themes are pretty well established.”

In addition to the high-volume attacks, Republicans are hoping to retain congressional majorities through their voter targeting and turnout expertise that even Democrats admire.

Because the stakes are so big, the intensity has been ratcheted much higher than in recent campaign cycles. Republicans, who only a couple weeks ago were braced for the possible loss of both chambers, seemed to regain their footing somewhat last week and now suggest that they can keep the Senate even if they lose the House.

Democrats need to win six seats in the Senate and 15 in the House to take control. In private, Republicans concede they are in big trouble in the House and Democrats acknowledge that their shot at the Senate may be slipping away as many Republican candidates seem to be benefiting from hard-hitting ads in key states. Republicans also have concluded that the damage was short-lived from the scandal involving former Rep. Mark Foley's sexually explicit e-mails to congressional pages.

“It seems like Republican candidates have caught a little puff of wind here as we move away from the Foley business,” Republican strategist Rich Galen said.

Charlie Black, who has been advising Republican candidates back to Ronald Reagan, also has begun to feel less pessimistic. “It looks like we have crept back up some,” he said Friday. “It's not huge, but I think we bottomed out the middle of last week.”

Both sides agree that the key will be whether conservatives who have grown disenchanted with Bush, the war or the Republican-led Congress stay at home or go to the polls simply to avert a Democratic Congress.

Black said the final week is crucial to nudging those conservatives to go vote. “The last seven days is when you have to get your (wavering) voters motivated to turn out,” he said.

To that end, the president and Republican candidates and their ads will spend the final days hitting issues dear to the heart of conservatives – the border fence, immigration, gay marriage, tax cuts and homeland security.

Republicans believe they were blessed when a narrowly divided New Jersey Supreme Court ruled last week that gays are entitled to the same legal benefits as traditional married couples. Galen has urged Republican candidates to link that ruling with the woman who would become speaker if the Democrats take control – Rep. Nancy Pelosi of San Francisco.

“I would say that if Democrats control Congress then you'll have Sister Boom-Boom as the clerk of the House,” he said. “So if that's what you want, then stay home and don't vote.”

He said the gay marriage issue may only change 2 percent of the vote. “But that's a big number if you're sitting on a 43-43 race.”

Galen credited the spate of negative ads with bringing Republicans back within striking distance.

“Negative ads always work,” he said. “Human beings are hard-wired to love gossip. We all deny it but we're all lying to ourselves. Negative ads are nothing more than highly distilled 30 seconds of gossip and that's why they work. We will believe bad information about somebody no matter how much good information we know.”

In recent days, Republicans have asked voters to believe that some Democrats have failed to pay their taxes, supported pedophilia, studied sexual habits of teens, promoted sex between black men and white women, written dirty novels, freed serial killers and want America to lose the war on terror.

Democratic strategist Maryanne Marsh said Democrats are braced for more “fear and smear” from Republicans in the final days.

“The only thing they are running on is trying to tear apart Democrats on a personal level,” said Democratic pollster Mark Mellman, who doubts the national mood has shifted in the last week. “If they bottomed out, they bottomed out at a really low point. We still see a big anti-Republican wave.”

Both sides acknowledge that Republicans in recent cycles have been much better than Democrats at targeting and turning out their voters. “I tip my hat to them,” Marsh said. “Their microtargeting, the way they use e-mail and direct mail and their 72-hour program are all exceptional.”

“Microtargeting,” which has been perfected by the GOP, allows the party to get specific messages to any group they want, from male snowmobilers to female bowlers.

But Democrats hope their enthusiasm can counter that. “Our base is much more enthusiastic, much more turned on, much more likely to turn out this year than is the Republican base,” Mellman said.