The six-week delay in Nigeria's presidential election has raised red flags both in the international community and among local political and civil rights groups, with many concerned about the independence of the country's electoral commission and whether the military hierarchy had too much say in the matter.

President Goodluck Jonathan and his chief rival, former military dictator Muhammadu Buhari, are facing off in what is probably the tightest presidential contest in the history of Nigeria, Africa's most populous nation and its economic powerhouse, so any change like moving back election day is seen as suspicious and a possible game-changer.

Many international observers had already arrived in the country and foreign journalists were struggling to obtain visas when Nigeria's electoral commission announced Saturday it was postponing the Feb. 14 presidential and legislative elections until March 28.

"Political interference with the Independent National Electoral Commission is unacceptable," U.S. Secretary of State John Kerry said. "It is critical that the government not use security concerns as a pretext for impeding the democratic process."

Nigerian elections were blatantly rigged until 2011, which was the fairest election ever seen in the country. But political shenanigans and charges by civil rights groups that the police and military favor Jonathan's party have raised skepticism that the next election will be proper. A recently released Gallup poll indicates the confidence level declined from 51 percent in 2011 to 13 percent last year.

For weeks, electoral commission chairman Attahiru Jega had resisted pressure to delay the vote, insisting as late as Feb. 5, 48 hours before his postponement announcement, that the commission was ready to hold the elections as scheduled. Jega had already acknowledged that some 30 million of the 68.8 million voters' cards had not been delivered to voters. By Feb. 6, the number had risen to 48.2 million delivered.

On Feb. 2, the chief of defense staff and chief of army staff had assured a meeting in Abuja, the capital, that they were ready to help secure the elections. On Feb. 6, they wrote to the electoral commission that that would not be possible.

The next day, Jega said it would be "highly irresponsible" to ignore warnings from national security advisers and intelligence officers that the military was overstretched, planning a "major operation" against Islamic extremists in the northeast that would make it unable to perform its traditional role of supporting the police in securing elections.

The opposition All Progressives Congress coalition concluded: "It is difficult not to come to the obvious conclusion that the Military High Command is in an unholy and dangerous alliance with the ruling party, the PDP, to subvert the democratic will of the people."

Nigeria's military tried to reassure Nigerians, saying "the military will remain professional, apolitical and non-partisan."

The delay does not appear to favor either side. Jonathan's campaign could suffer as it provides more time for ordinary Nigerians to feel the economic impact of oil prices that have halved in recent months — 80 percent of government revenue comes from petroleum — and the plummeting naira currency.

Though Buhari's coalition opposed the postponement, it stands to gain from any additional votes cast in the northeast, where Jonathan has become hugely unpopular because of his mishandling of the Islamic uprising. The three northeastern states under a state of emergency have about 4.5 million registered voters.

But Buhari's campaign could find itself short of funds.

"The delay could weaken Buhari's hand by draining his campaign of resources needed to win over the next six weeks — namely money," said the Eurasia Group, a political risk research and consulting firm.