At the same time, the government has heavily intervened to slow the decline of the Turkish lira, mostly by selling foreign currency reserves. During one week in early May, the reserves declined by $7.6 billion to $60.8 billion, according to central bank data, the largest such decline in more than two decades.

To address that, Mr. Erdogan has reached agreements with countries including Qatar, Russia and Saudi Arabia that would help shore up reserves in Turkey’s central bank. Saudi Arabia announced a $5 billion deposit in March, and Russia agreed to delay at least some of Turkey’s payment for natural gas imports until after the election.

The terms of most of these agreements have not been made public, but economists said they were part of a short-term strategy by Mr. Erdogan more focused on winning the election than on ensuring the country’s long-term financial health.

Should Mr. Erdogan win, as many analysts expect he will, few expect him to dramatically change course.

“I don’t think the current government has a plan to fix this because they don’t admit that these problems are due to policy mistakes,” said Selva Demiralp, a professor of economics at Koc University in Istanbul. “I don’t see a way out for the current government.”