Gen. Salou Djibo, who led a coup last February that ousted President Mamadou Tandja after he overstayed his term, called on voters to go to the polls and cast his own ballot early in the presidential and parliamentary elections.
"This new start should allow the authorities, freely elected by the people, to devote themselves to the development of Niger," Djibo told reporters.
Although rich in uranium, this African nation of 15 million is among the bottom of the U.N.'s Human Development Index, which ranks countries in order of general well-being. Its northern deserts and even the capital, Niamey, have been the scene of kidnappings linked to al-Qaida terrorists.
Long lines formed in Niamey hours before polling stations opened. Some opened late due to missing polling staff and materials, but voting appeared to be calm.
"I have been here since 6:30 a.m," voter Mehaou Mounkaila said. "I want to exercise my civic right because today is a very important day for us Nigeriens."
The country's 6.7 million registered voters are choosing between 10 presidential candidates, including the first female presidential hopeful, and there are also 116 legislative races nationwide.
Presidential front-runners include former Tandja prime ministers, Seini Oumarou and Hama Amadou, as well as Mahamadou Issoufou, the longtime anti-Tandja leader whose party dominated local and regional elections earlier this month.
Mahamane Ousmane, who won the presidency in Niger's first democratic polls in 1993, is also a presidential candidate but not a front-runner. Ousmane was toppled in a 1996 coup and later led Parliament until Tandja dissolved it in 2009.
Tandja gained power a decade ago through the ballot box and won elections again five years later but later took a dictatorial turn, abolishing parliament and the nation's highest court. In 2009 he forced through a new constitution, which critics denounced as illegal, granting him three more years in power and the chance to run for president as many times as he wanted.
When military leaders arrested Tandja almost a year ago after blowing a hole through the front gate of the presidential palace, they vowed to restore civilian rule. Several coup leaders engineered a similar move in 1999, and went on to oversee free elections that set the stage for a decade of democratic peace. The junta recently transferred Tandja from house arrest to prison after charging him with graft.
Many in Niger supported the military's action last year but there's skepticism the elections will fully break a long cycle of coups, countercoups and political maneuvering in the landlocked country since it won independence from France in 1960.
Still, some say Niger's immediate future looks secure. A new constitution approved by referendum in October - the country's seventh in 50 years - gives the military until April 6 to pass the reins back to civilian hands.
"The military has already planned its departure for April 6. There is no doubt they will leave, no matter who wins the election," said Niger political analyst Souley Adji.
Security forces and observers from the European Union, the African Union and the 15-nation regional bloc known as ECOWAS were present at polling stations. But EU observers said they would not be deploying to the country's northern Agadez region for security reasons.
Al-Qaida in the Islamic Maghreb, or AQIM, has turned broad swaths of desert from Niger to Mauritania into no-go zones for Westerners. AQIM gunmen even grabbed two Frenchmen from a restaurant in Niger's capital in January. The men were found dead less than 24 hours later following a failed rescue attempt by forces from France and Niger near the Malian border.
AQIM is believed to still hold five French nationals along with hostages from Madagascar and Togo who were all kidnapped from a French uranium mine in Niger in September.
Security analysts and Niger's interim government say AQIM poses little threat to the elections and Niger's citizens though.
"We held the local and regional elections without problem, and campaigning for this round has gone without incident," said Interior Ministry Secretary-General Ibrahima Mory.
Niger's electoral commission says it could take up to a week to tally and announce provisional results, which would need to confirmed by the constitutional court within two weeks.
If there is no clear presidential victor, the top two candidates will participate in a run-off election in March.
Associated Press writer Anne Look in Dakar, Senegal contributed to this report.