With Trotsky finally on the sidelines, the Zinoviev-Kamenev-Stalin triumvirate began to crumble early in 1925. The two sides spent most of the year lining up support behind the scenes. Stalin struck an alliance with a Communist Party theoretician and "Pravda" editor Nikolai Bukharin and Soviet prime minister Alexei Rykov. Zinoviev and Kamenev allied with Lenin's widow, Nadezhda Krupskaya, and Grigory Sokolnikov, the Soviet Commissar of Finance and a non-voting Politburo member. The struggle became open at the September 1925 meeting of the Central Committee and came to a head at the XIVth Party Congress in December 1925. With only the Leningrad delegation behind them, Zinoviev and Kamenev found themselves in a tiny minority and were soundly defeated. Zinoviev was re-elected to the Politburo, but his ally Kamenev was demoted from a full member to a non-voting member and Sokolnikov was dropped altogether, while Stalin had more of his allies elected to the Politburo. Within weeks of the Congress, Stalin wrested control of the Leningrad party organization and government from Zinoviev and had him dismissed from all regional posts, leaving only the Comintern as a possible power base for Zinoviev.