However, the president's grip on his party has been tightened this year, with former Prime Minister Ahmet Davutoglu and former Deputy Prime Minister Ali Babacan resigning and seeking to form rival movements for Erdogan's party.
Hundreds of thousands of AKP members have resigned over the past year, according to figures on websites.
Former officials told Reuters the resignation was a sign of disappointment felt by many who see their party increasingly taking authoritarian tendencies.
"Almost every day, colleagues who have played roles in the party since day one choose a new path," said a former senior official who did not want to be named.
And added "Many friends want a fresh start and join Babacan and Davutoglu."
Juma Istan, a supporter of Davutoglu who resigned from the party this month, says the AKP was targeting those who left as traitors.
Another former party member said he and other colleagues resigned after feeling exclusion.
Istan added" the government has announced that everyone not member in its party he is traitor.
An AK Party official told Reuters Babacan and Davutoglu did not enjoy broad support and said he did not expect a mass resignation.
However, the ruling party already relies on a coalition with the far-right Nationalist Movement Party (MHP) for its majority in parliament, and Erdogan needs more than 50 percent of the vote to retain the presidency in the next election.
This is due to happen in 2023, although some commentators have said that a major shift in the political landscape - such as the split of a large number of AKP members in parliament into new parties - could force early elections.
Relatively low support may prove crucial. The ruling party suffered a serious blow this year in local elections, losing five of the country's largest provinces to the opposition.
"Erdogan's popularity over the past seven years ... is generally declining," Gareth Jenkins of the Stockholm-based Institute for Security and Development told Reuters.
Jenkins added that Babacan's party would withdraw support from Erdogan, with Erdogan making "mistakes and miscalculations" in the absence of any good advice.
He stressed that the AKP "has become more detached from experience and efficiency, and is increasingly surrounded by inefficient men."