"The highly remarkable feature of our revolution is that it has brought about a dual power. This fact must be grasped first and foremost: unless it is understood, we cannot advance....What is this dual power? Alongside the Provisional Government, the government of bourgeoisie, another government has arisen, so far weak and incipient, but undoubtedly a government that actually exists and is growing—the Soviets of Workers’ and Soldiers’ Deputies." (V.I. Lenin, "The Dual Power". Full text at https://www.marxists.org/archive/len...917/apr/09.htm)
Essentially what happened was the Tsar was overthrown so quickly in the February Revolution that the proletarian liberating forces were sort of paralyzed; they lacked the unity, strength, and frankly the confidence to completely take over and fill the governing role of the former monarchy to establish the dictatorship of the proletariat. Due to Lenin's lack of presence in the first month or so after the February Revolution because of his exile, the Bolsheviks actually supported allowing the bourgeois Prov. Gov. to regain control and allow the liberal reformism to take hold of the country again. Because both the Mensheviks and the Bolsheviks (at least until Lenin's return) supported bourgeois reformism, the Prov. Gov. was able to take hold with worker's soviets existing alongside it to sort of provide the Prov. Gov. with 'input' on workers' reforms to make. However, the bourgeois government was, like all bourgeois governments are, too preoccupied with the war to appease the peasants of Russia, which allowed the Bolsheviks to take control of the soviets and therefore ultimately gain a mass following of the proletariat, giving them the power to overthrow the Prov. Gov. So, the dual power (at least in the case of Russia) was letting the petty bourgeois take control while the workers organized and united, let the bourgeois get preoccupied with their foreign stuff like they always do (which allowed for the Bolsheviks to gain the support and win the hearts of the workers), and then strike after the Prov. Gov. lost their popular support, which included most of the military.
The dual power system is highly unstable, which necessitates the overthrowing of one government and the gaining of control by the other. What really matters to ensure the alternative government is the people's support (Che Guevara saw the support of the people as the greatest asset to revolutionaries, and said that without the support of the people very little can be accomplished, but with it anything is possible. He mentions the support of the people about every other sentence in Guerrilla Warfare).


