Independent politician Yekaterina Duntsova wanted to run on a platform to end the war with Ukraine.
But the electoral commission voted unanimously to reject her candidacy three days after her application, citing 100 “mistakes” on her form.
Ms Duntsova said she would appeal the decision at the Supreme Court.
The commission said 29 people have so far filed to run for the presidency. But after today’s decision, Mr Putin remains the only candidate to be able to register as a candidate.
What’s worse is that people believe in those numbers, although hopefully not all do