* Candidate has right to seek two-week delay
* President Serzh Sarksyan seen winning Feb. 18 vote
By Hasmik Mkrtchyan
YEREVAN, Feb 10 (Reuters) - An Armenian presidential candidate who was shot has appealed for this month's election to be delayed to allow him more time to campaign, raising concerns over instability in the former Soviet republic.
Paruyr Hayrikyan, who was shown on television looking pale and bedridden with his arm in a cast, had initially said he would not seek a postponement.
He changed his mind just few hours before a deadline to apply to the Constitutional Court to delay the Feb. 18 vote after doctors advised him to remain in hospital.
"We've applied the Constitutional Court with a request to postpone the election for two weeks due to Paruyr Hayrikyan's health problems and the fact that he can't campaign," Vrezh Zatikyan, the candidate's aide, told Reuters.
An outsider in the race in which President Serzh Sarksyan is widely expected to win a new five-year term, Hayrikyan was shot in the shoulder on Jan. 31 near his home in the capital Yerevan.
Doctors have removed the bullet and said Hayrikyan's life was not in danger, but he remained in hospital on Sunday.
The Constitutional Court must rule within four days on whether to delay the vote in the country of 3.2 million - a decision which will largely depend on doctors' evaluation of whether the candidate is well enough to campaign.
Any delay has the potential to stir protests by supporters of candidates who believe the decision favours one party or another.
Violence flared after Sarksyan's election in 2008, leaving 10 people dead when police clashed with supporters of former president and opposition candidate Levon Ter-Petrosyan who protested for days on the streets of the capital.
Hayrikyan, 63, a pro-Western former Soviet dissident, said hours after the shooting that he suspected a foreign secret service and suggested he was referring to Russia, which is its main ally and has a military base on its territory.
Police said on Friday two suspects who had admitted their guilt were arrested, although any motive was not immediately clear.
Formerly known as the Soviet Union's manufacturing hub, Armenia has remained firmly within Moscow's radius since its industry fell apart with the 1991 Soviet collapse.
Today, its economy is still struggling from the effects of a war with neighbouring Azerbaijan in the 1990s that left the tiny landlocked nation regionally isolated. Two of four neighbours, Turkey and Azerbaijan, have closed their borders to Armenia.
Hayrikyan leads an opposition party, the National Self-determination Union, and ran for president in 2003. (Writing by Margarita Antidze; Editing by Alison Williams)