WASHINGTON – Congress certified President Bush’s re-election yesterday, but only after Democrats forced a challenge to the quadrennial count of electoral votes for just the second time since 1877.

Mr. Bush’s Election Day triumph over John Kerry, the Democratic Senator of Massachusetts, was never in doubt. After a near four-hour delay to consider and reject a dispute over voting in Ohio, lawmakers in joint session affirmed Mr. Bush’s 286-251 electoral vote victory – plus a single vote that a “faithless” Kerry elector cast for his running mate, John Edwards. A total of 270 votes are needed for victory.

“This announcement shall be a sufficient declaration of the persons elected president and vice president of the United States for the term beginning January 20, 2005,” Vice President Cheney, who presided over the session, read without emotion when the final votes were tabulated.

In a drama that was historic if not suspenseful, Rep. Stephanie Tubbs Jones, an Ohio Democrat, and Senator Boxer, a Democrat of California, formally protested that the Ohio votes “were not, under all known circumstances, regularly given.” That, by law, required the House and Senate to convene separately and debate the Ohio irregularities.

Ms. Boxer, Ms. Tubbs Jones, and several other Democrats, including many black lawmakers, hoped the showdown would underscore the problems such as missing voting machines and unusually long lines that plagued some Ohio districts, many in minority neighborhoods, on November 2.

“If they were willing to stand in polls for countless hours in the rain, as many did in Ohio, than I can surely stand up for them here in the halls of Congress,” Ms. Tubbs Jones said.

Democratic leaders distanced themselves from the effort, which many in the party worried would make them look like sore losers. Mr. Bush won Ohio by 118,000 votes and carried the national contest by 3.3 million votes, and Mr. Kerry himself – meeting with troops in the Middle East – did not support the challenge.

The debates were tinged by memories of the 2000 election, when Mr. Bush edged Democrat Al Gore after six weeks of recounts and turmoil in Florida.

“There’s a wise saying we’ve used in Florida the past four years that the other side would be wise to learn: Get over it,” said Rep. Ric Keller, a Florida Republican.

The joint session began as required by law at 1 p.m. EST, with Mr. Cheney presiding as the Senate’s president and about 100 lawmakers in attendance.

One by one and in alphabetical order, certificates of each state’s electoral votes were withdrawn from ceremonial mahogany boxes and read aloud. The session usually goes quickly, but when Ohio’s votes were read 16 minutes into the meeting, Ms. Tubbs Jones and Ms. Boxer issued their challenge to Ohio’s 20 electoral votes. The state had put Mr. Bush over the top.

By law, a protest signed by members of the House and Senate requires both chambers to meet separately for up to two hours to consider it. The Senate session lasted just over an hour and ended when the chamber voted 74-1 to uphold Ohio’s votes, with Ms. Boxer the lone vote in opposition. The House used its full time and upheld the Ohio results, 267-31.

For Ohio’s votes to be invalidated, both Republican-controlled chambers would have had to back the challenge.

The last time the two chambers were forced to interrupt their joint vote-counting session and meet separately was in January 1969, when a “faithless” North Carolina elector designated for Richard Nixon voted instead for independent George Wallace. Both chambers agreed to allow the vote for Wallace.

The previous challenge requiring separate House and Senate meetings was in 1877 during the disputed contest that Rutherford Hayes eventually won over Samuel Tilden.

Supporters of the challenge repeatedly said they had no desire to overturn the election. Many who spoke in favor of the protest even voted against it in hopes of clarifying what they said was the real issue – the need to make the country’s voting systems fairer and to prevent fraud.

“Our people are dying all over the world…to bring democracy to the far corners of the world. Let’s fix it here,” Ms. Boxer said.

But that didn’t stop Republicans from casting Democrats as trying to subvert the election results.

Rep. Candice Miller, a Republican of Michigan, said the Democratic complaints were “outrage based on fantasy conspiracies.” House Majority Leader Thomas DeLay, a Republican of Texas, called the effort “a shame” and its goal “not justice but noise.” At the White House, spokesman Scott McClellan said it was time to move forward and “not engage in conspiracy theories or partisan politics of this nature.”

Senate Democratic aides said Senator Reid, a Democrat of Nevada who is the new Senate minority leader, initially opposed challenging the Ohio vote, and questioned Ms. Boxer about it when she told him she would join the protest.

He spoke briefly during the Senate debate, saying, “The sacrifice of our military demands that we ensure that our own elections are fair.”

House minority leader Nancy Pelosi, a California Democrat, declined to directly answer reporters’ questions about whether she supported the move. But she, too, spoke during the House debate, saying of the challengers, “This is their only opportunity to have this debate while the country is listening.”