Turkmenistan's acting president has emerged as the likely successor to Saparmurat Niyazov, who died last week after 21 years of autocratic rule.
Gurbanguly Berdymukhamedov was health minister
Turkmen legislators amended the rules to allow Gurbanguly Berdymukhamedov to run, along with five other candidates, in February's presidential elections.
And the country's top election official has already said Mr Berdymukhamedov is a "worthy" successor to Mr Niyazov.
Exiled opposition leaders say they will run but hopes of real change are slim.
'Missing' opposition candidate
Candidates standing in the 11 February election will reportedly be able to address voters, but only through meetings organised by local authorities, and through the media, which is state owned.
Their campaigns must also be funded from the state budget, the Associated Press quotes the new election law, published in Turkmen media, as saying.
Mr Berdymukhamedov, Turkmenistan's People's Council and election officials have all pledged a democratic ballot.
But analysts say Mr Berdymukhamedov has emerged as Mr Niyazov's heir apparent in recent days and is likely to beat the other five presidential candidates, who are little-known officials.
Mr Berdymukhamedov's candidacy received unanimous backing from the 2,500-strong People's Council, which amended the constitution on Tuesday to allow him to stand.
Before the amendment, acting presidents were banned from contesting elections.
Election chief Murad Kariyev said on Tuesday he would "do everything" he could to ensure Mr Berdymukhamedov won "because he is a worthy candidate".
Opposition groups, most of whose leaders are now in exile abroad, have said they will put forward candidates for the election. But without the People's Council approval, they have little chance of running.
One group -the United Democratic Opposition of Turkmenistan (UDOT) - said its candidate Nurberdy Nurmammedov went missing in the capital Ashgabat soon after Mr Niyazov's death.
Gold teeth ban
Little is known about Mr Berdymukhamedov because Mr Niyazov never allowed strong political leaders to come to prominence, the BBC's Natalia Antelava says.
What is known, she says, is that Mr Berdymukhamedov is 49 years old, was deputy prime minister at the time of Mr Niyazov's death and is a rare survivor of the late president's many purges.
Saparmurat Niyazov's funeral took place earlier in the week
He trained as a dentist before becoming health minister in 1997, presiding over the country's deteriorating health system.
He also implemented one of Mr Niyazov's most controversial decrees - closing all rural hospitals and replacing 15,000 doctors with military physicians in 2005.
Mr Berdymukhamedov was in charge when President Niyazov banned gold teeth - a sign of affluence and wealth in Turkmenistan - and advised his people to chew on bones, which he said were good for their teeth.
The elections in the energy-rich Central Asian republic will be followed with interest by international observers.
President Niyazov wielded absolute power and fostered a cult of personality around himself and his family during his two decades of rule.
Mr Berdymukhamedov has vowed to follow in the late president's footsteps, but keeping together a country created almost entirely around Mr Niyazov will be a huge challenge, our correspondent says.