Russian Constitutional Monarchy in 1905

[Peter the Lefty]

      Here's an interesting one.  In 1905, to respond to the growing street protests and strikes, instead of opting for half measures, Tsar Nicholas II introduces a full constitutional monarchy wherein he is a mere figurehead, and all men, regardless of class, have an equal vote in Duma elections. 
      Does the RSDLP win the first election, and if so, would Julius Martov likely be the first PM, or would it still be Lenin?