The surprise broadcast last week of a videotape from Osama bin Laden injected an element of uncertainty into the final days of the presidential campaign, stirring speculation about which candidate would be most affected.

Would the fresh image of the defiant al Qaeda leader feed public fears of terrorism and thereby intensify support for President Bush, who had made the war on terrorism the core of his appeal for a second term?

Or would it remind Americans that Bush still had not caught the elusive terrorist and thereby push voters to Sen. John F. Kerry, who had argued that U.S. forces under Bush had become distracted by Iraq?

Polls taken over the weekend and outside voting stations on Tuesday indicate that bin Laden's reappearance may have cut both ways -- and ultimately had little net effect on the election's outcome.

A weekend survey by NBC News and the Wall Street Journal found a large share of likely voters -- 74 percent -- knew about bin Laden's message, which warned Americans to stop threatening the security of Muslims.

Asked whether the statement made them more inclined to vote for one U.S. presidential candidate or another, 24 percent said Bush, 12 percent said Kerry -- and 62 percent said it made no difference. A Sunday poll by Marist College found that 46 percent said they were "more favorable to Bush" from what they knew of the bin Laden videotape, while 43 percent said they were "more favorable to Kerry."

On Tuesday, a nationwide exit poll conducted for a consortium of news organizations found that 56 percent of voters considered the bin Laden videotape "important," according to results released by CNN.

Of those, half voted for Bush, and half for Kerry.

"I saw nothing to indicate it helped or hurt Bush," said Andrew Kohut, director of the Pew Research Center, which did its own polling on the question over the weekend.

Kohut said a majority of the "late-decider" voters opted for Kerry, but he rejected the idea that they were driven to do so by new concern about bin Laden.

"I don't think the public saw anything in the videotape that frightened them more than they already were, or that gave them any insight into the problem we face," he said.