Moscow, Aug. 17 -- After a monthlong hunger strike, it's a struggle for Lyubov Sobol to even raise her hands. Every gesture is difficult for the frail 31-year-old political activist.

This summer's wave of anti-government protests in Moscow propelled her to the forefront of Russia's opposition movement. Her name rang out on the streets of the capital, packed with demonstrators angered by the refusal of election authorities to allow independent candidates, including Sobol, on the ballot for the Moscow Duma, or city council.

Sobol has been the prime target of attacks by both the Kremlin-friendly media and election officials.

"The attitude to me is different because I work harder than others and I don't let people get away with lies," Sobo...