Financial markets are placing nearly 70 percent odds on the Federal Reserve raising interest rates in late October. Federal Reserve officials, led by Kevin M. Warsh, hold their next policy meeting just days before the midterm elections.

The Fed strives to be politically independent and asserts that it does not factor the electoral calendar into its policy debates. There are numerous instances in which the central bank either raised or lowered rates in the months leading up to or directly before an election because the economic conditions warranted it. But at a time when Mr. Trump has accused the Fed of being politically motivated and has taken direct aim at individual policymakers for not complying with his demands for substantially lower borrowing costs, the economic rationale needs to be ironclad.

Financial markets this week have boosted bets that the Fed will risk drawing Mr. Trump’s ire and proceed with another quarter-point increase that will lift rates to a new range of 4 percent to 4.25 percent at its meeting on Oct. 27-28.