Voters in Turkmenistan headed to the polls Sunday in an election that is expected to re-elect President Kurbanguly Berdymukhamedov.

The 54-year-old is president, prime minister, commander of the armed forces and head of the only political party in the former Soviet republic, which borders Iran and Afghanistan.

Analysts say Mr. Berdymukhamedov is most likely assured to win because his token political challengers are his government friends.

The Central Asian nation holds four percent of the world's gas reserves and has oil fields in the Caspian Sea. The president has been keen to diversify the country's gas sales in order to attract investment by engaging foreign governments.

Turkmenistan is the most secretive of the post-Soviet countries in Central Asia. Nearly three million Turkmen are allowed to vote – that is about half of the population. The Organization for Security and Cooperation in Europe says it will not send vote monitors to the region because of limited freedoms and lack of political competition. Only Eritrea and North Korea rank lower than Turkmenistan in the press freedom index by the international journalist advocacy group Reporters Without Borders.

Five days before registration of presidential candidates ended, a law allowing opposition candidates to register came into force. Analysts say the law will not affect the dominance of the president's party.