KAYAWA, Nigeria – Nigerians chose their president in an election Saturday many hoped would show Africa's most populous nation could hold a credible vote without the violence and rigging that marred previous ones, though children cast ballots and party officials helped others press their inked fingers to paper.

Despite widespread security concerns after bombs hit a vote-counting center and a polling station during last weekend's legislative elections, voting in the oil-rich country was largely peaceful Saturday though a police officer was fatally shot in the volatile northeast.

"In recent decades, Nigeria had come to be known for flawed elections. People outside and Nigerians themselves had come to believe that elections could not reflect the will of the people. But, today people showed that they can change that," former Botswana President Festus Mogae, who led the Commonwealth Observer Group, said.

"We seem to be witnessing a giant of Africa reforming itself and putting its house in order," Mogae said.

The chief European Union observer also said most stations opened on time, and that observers only saw a few cases of missing voting materials. But in the remote villages of northern Nigeria where opposition candidates are drawing their support, some of the voters were smooth-cheeked boys not even 5 feet (1.5 meters) tall, wearing clothes two sizes too big for them.

Leaders at the polling station in Doge Game shouted at the children in the local Hausa language to go back into a nearby classroom until an Associated Press reporter left the scene. Nigerians must be 18 in order to cast ballots, but Mogae said that underage voters had been isolated.

Elsewhere, party officials helped people ink their fingers and mark their ballots. One party worker even accompanied an elderly woman to drop off her ballot in the box despite regulations banning them from voting stations. And at one collation center in the megacity of Lagos, volunteers carried blank ballots without supervision from election officials though officials said the number of actual votes cast had already been recorded elsewhere.

Voters on Saturday were deciding whether to keep incumbent President Goodluck Jonathan — a Christian from the south who only took power because the Muslim president died following a lengthy illness and absence from office.

Jonathan is the candidate for Nigeria's long-dominant ruling party and is the clear front-runner, but several other candidates threaten to siphon off enough votes that it could go to a second round for the first time since Nigeria became a democracy 12 years ago.

Jonathan told reporters Saturday that Nigeria was experiencing a "new dawn" with the election, and that while he expected to win he would not interfere with the electoral process. Still, he said he hoped the weekend vote would be conclusive.

"I pray I don't go into a by-election because of the cost implications," he said wearing his signature black bowler hat and traditional caftan as he was surrounded by throngs of cameramen in his home state of Bayelsa. "We pray that whoever will win, will win."

The opposition candidates are capitalizing on discontent with the ruling People's Democratic Party. While voters were careful not to mention it by name, they blamed current leaders for a lack of a clean drinking water, schools, electricity and jobs in this country where most live on less than $2 a day.

"They don't care for the country," said Lawan Musa, 50, a local farmer who turned up Saturday to vote at a dilapidated tin-roof schoolhouse in the northern village of Kayawa. Inside one dirty classroom, a chalkboard bore questions for a computer science exam but the school doesn't even have a computer or constant electricity.

To win, Jonathan must receive a minimum level of support from across this enormous West African country of 150 million — a complicated formula somewhat similar to the American electoral college system. He cannot win the presidency outright unless he carries at least a quarter of the votes cast in at least two-thirds of states and the capital.

Nigeria, though, is largely split between a Muslim north and a Christian south. While Jonathan is embraced in the nation's south, many in the country's Muslim north believe one of their own should have had another turn after the Muslim president died in office in May 2010.

Among those looking to take away key votes from Jonathan in northern Muslim constituencies is a hometown candidate — former military ruler Muhammadu Buhari. He ruled Nigeria shortly after a 1983 coup, executing drug dealers and going after corrupt officials while also stifling freedom of speech and jailing journalists. Former anti-corruption czar Nuhu Ribadu is also running.

Buhari, who has filed court challenges over voting irregularities after previous losses at the polls, said he would abide by Saturday's results no matter what.

In Lagos, streets normally clogged with traffic, vendors and pedestrians were desolate Saturday because of restrictions limiting people to their neighborhoods. Young boys in one neighborhood took advantage of the deserted roads to set up soccer goal posts. Life resumed soon after the vote: In the densely populated neighborhood of Mushin, women promptly set up shop on the roadside to sell bunches of plantain and motorcycle taxis zoomed on the main road.

Jonathan's campaign posters feature prominently here, and voter Ogah Emmanuel said he would back the incumbent.

"He has a vision for this country. I will just try and give him the mandate to rule again and see the next four years," Emmanuel said. "He has promised us, as youths, what he's going to do (for us). We know he's going to do it."

But Ita Emmanuel, a 32-year-old social worker living in Lagos, said he was voting for change.

"We've had some people for 12 years and our lives have not changed, I don't think that the same people can bring change in the next four years," he said.

Many hope Saturday's vote will help Nigeria atone for years of marred polls. International observers roundly rejected Nigeria's 2007 poll as being rigged and marred by thuggery, though it represented the nation's first civilian-to-civilian transfer of power.

Both Jonathan and the leader of the country's Independent National Electoral Commission promised a free and fair vote Saturday. However, election workers clamored for life insurance and police protection.

During legislative elections last weekend, violence erupted in northeastern Nigeria, where the radical Islamic sect Boko Haram operates, leaving a hotel ablaze, a politician dead and a polling station and a vote-counting center bombed.

On Saturday, violence flared again in the region, with authorities blaming the Islamic militants for fatally shooting a policeman at a polling station. Earlier in the morning, a blast went off in a residential neighborhood of Maiduguri though there were no injuries. Several people were later arrested in connection with the attacks.

Mallam Baba Hassan, 25, a commercial motorcycle operator, said the violence was one reason he voted for change with opposition candidate Buhari.

"The political changes could only be affected by us by voting for a presidential candidate that could address endless power outages, poverty and insecurity to lives and property," he said. "The Boko Haram bomb blasts have not scared us from exercising our civic rights."

http://news.yahoo.com/s/ap/20110416/ap_on_re_af/af_nigeria_election