ANKARA (Reuters) - At least 200 top Turkish civil servants, many from the intelligence, finance and transport sectors, have quit their posts to run in parliamentary elections later this year.

The flurry of resignations came ahead of the deadline on Tuesday for government officials to step down if they plan to be candidates in June's vote.

Most hope to represent the ruling AK Party founded by President Tayyip Erdogan, which is expected to maintain its dominance, and loyalty to the head of state is expected to be a major factor in who gets selected.

News has so far been dominated by Turkey's powerful spy chief and key Erdogan confidant Hakan Fidan, who quit last week to run, in spite of opposition from his former boss.

Other prominent figures vying for about 70 seats being vacated by AKP deputies include Istanbul stock exchange chairman Ibrahim Turhan and Finance Ministry undersecretary Naci Agbal. The party veterans are leaving after reaching the AKP's self-imposed three-term parliamentary limit.

The general manager of Turkish State Railways, a provincial police chief and a university rector have also joined the crowded field. The influx will be the largest shake-up of the AKP since it swept to power in 2002.

"The newly named candidates will be more dynamic, expert on their subjects, and will represent transformation in some areas," a top AKP official told Reuters.

Erdogan has placed high priority on winning a strong parliamentary majority to allow the AKP to vote through constitutional changes to bolster his powers as head of state.

Two of his top advisors, Aydin Unal and Mustafa Isen, as well as several key aides to Prime Minister Ahmet Davutoglu also quit their posts.

Erdogan's public opposition to Fidan's resignation took many Turks by surprise and raised the possibility of a split between Erdogan and Davutoglu.

Speaking this week during a trip to Colombia, the president described Fidan, who has been tipped as a potential foreign minister, as his "keeper of secrets". "Perhaps assurances were made to him, I don't know. But I told him very openly and clearly, 'I don't find your resigning correct'," Erdogan stated.

Former Central Bank governor Durmus Yilmaz, who has publicly criticised Erdogan for pressuring the central bank to change economic policy, will be a candidate for the nationalist MHP.

Outgoing MPs include Energy Minister Taner Yildiz and Deputy Prime Minister Ali Babacan, the darling of foreign investors.