* Sarksyan had wide lead in polls before vote
* Voters see stability in voting for incumbent
* Campaign tainted by assassination attempt on rival
By Hasmik Mkrtchyan
YEREVAN, Feb 18 (Reuters) - Armenians voted in a presidential election on Monday that is likely to hand incumbent Serzh Sarksyan a new five-year term, but the lack of any serious opposition and an assassination attempt on one of his rivals cast a shadow over the election.
Opinion polls suggest Sarksyan's victory is all but certain. He is on target to win more than 60 percent of the votes in the small, landlocked country in the South Caucasus, with the next of the other six candidates barely in double figures.
Sarksyan's supporters hope an election free of the violence and fraud that marred the last presidential poll in 2008, when 10 people were killed in clashes, would show the world the former Soviet republic is on the path to economic recovery after years of war and upheaval.
Political stability was a concern among a steady trickle of voters who headed to a polling station at a children's daycare centre in the capital, Yerevan.
"Sarksyan promotes the improvement of educated society, which is a guarantee of Armenia's future," said Artak Avetsyan, 31, a teacher who came to cast his ballot for the incumbent.
But with none of Sarksyan serious rivals in the opposition choosing to stand in the race, election observers expressed concerns over the democratic credentials of the vote.
Officials from the Parliamentary Assembly of the Council of Europe said they found apathy towards the election and a lack of confidence about the electoral process among the public when they visited the country in January.
There are also questions about security in a country that is locked in a dispute with neighbouring Azerbaijan over Nagorno-Karabakh, an ethnic Armenian-majority enclave inside Azerbaijan over which Armenians and Azeris fought a war in the 1990s. Sarksyan, 59, like many of his generation, is a veteran of that war.
Tensions over the mountainous enclave still pose a threat to peace in a region where pipelines take Caspian oil and natural gas to Europe.
Concerns about instability were underlined in an attempt to kill Paruyr Hayrikyan, 63, an outsider in the election. He was shot in the shoulder on Jan. 31.
Another outsider in the race, Andrias Ghukasyan, has been on a hunger strike since the start of the campaign to press demands for Sarksyan's candidacy to be annulled and for international observers to boycott the vote.
A third candidate, Arman Melikyan, has said he will not vote on Monday because he believes the election will be slanted in the president's favour. Other potential candidates did not take part in the race for similar reasons.
Casting her eye over the choices on the ballot, one early morning voter said Sarksyan was the most serious among them.
"I will vote for Serzh Sarksyan because he is the most trustworthy among the candidates. I am sure he will fulfil his promises," pensioner Anush Avdalyan, 80, said.
International observers from the Organisation for Security and Cooperation in Europe (OSCE) are monitoring polls, which opened at 8 a.m. (0400 GMT) and close at 8 p.m. (1600 GMT).
The first exit polls are expected a few hours after polls close and official results on Tuesday at 8 p.m. (1600 GMT). (Writing by Alissa de Carbonnel; Editing by Mohammad Zargham)