He doubled down on his attempts to cast Kilicdaroglu as an ally of outlawed Kurdish militants and scoffed at the opposition’s attempts to talk tough on security issues.
“Until yesterday, they were terrorist lovers,” Erdogan said of his rivals this week.
“You’re the coward who cooperates with terrorists,” Kilicdaroglu retorted on Twitter.
Some analysts view this campaign as Türkiye’s dirtiest in recent memory.
“I have followed dozens of campaigns since 1979, and I have never seen both candidates clearly lying to this extent,” the Cumhuriyet newspaper’s exiled former editor Can Dunar told AFP from Germany.
“This is the first time we are seeing such an insult-filled campaign.”
Most of Türkiye’s pre-election polls underestimated Erdogan’s level of support in the first round.
They now show him leading by five points or more – a margin that has instilled a sense of panic in Türkiye’s financial markets.
Indirect evidence shows Turks dumping their liras and stocking up on gold and dollars in anticipation of a currency crash after the election.
Official data show Türkiye’s central bank burning through US$25 billion in a month while trying to prop up the lira.
Türkiye’s net foreign currency reserves – an important measure of a country’s financial stability – have dropped into negative territory for the first time since 2002.
Capital Economics predicted that Erdogan would only relent and adopt more conventional economic policies “if Türkiye suffered a severe crisis and banking strains”.
“Our base case is that Türkiye manages to (just) avoid such a crisis, but the risks appear skewed towards a worse outcome,” the London-based consultancy said.
Kilicdaroglu’s decision to ally himself with a fringe far-right group this week nearly cost him the support of a pro-Kurdish party that accounts for a tenth of Türkiye’s vote.
The Kurdish-backed HDP decided Thursday not to back a poll boycott because this would only help extend Erdogan’s “one-man regime”.
But HDP co-leader Pervin Buldan did not hide her frustrations with Kilicdaroglu’s new approach.
“It is wrong to score political points off immigrants or refugees,” Buldan said.
Both Erdogan and Kilicdaroglu are now focusing on turnout.
“Our opponent is not Kilicdaroglu, but (voter) complacency,” Erdogan said in a televised interview Thursday.
Turnout in the first round reached a massive 87 per cent.
But it was slightly lower in Kurdish regions that supported Kilicdaroglu.
Data showed turnout among the 3.4 million Turks living abroad edging up in the second round from 1.7 million to 1.9 million.
Many of these voters are descendants of Turks who moved from poorer provinces to Western Europe and who traditionally support more conservative candidates.