Čolaković was born in the village of Ponikvice, near Nikšić, which at the time was located in the Kingdom of Yugoslavia's Zeta Banovina but which was previously and subsequently part of Montenegro.
He graduated from the Economic and Commercial School in Novi Sad and became involved in the labour movement, serving with the union of the Vrbas municipality for twenty years.
[7] The PUPS contested the 2007 Serbian parliamentary election in an alliance with the Social Democratic Party, and Čolaković received the third position on their combined list.
Čolaković was given the thirteenth position on the Socialist list and was chosen as part of the PUPS parliamentary delegation when the alliance won twenty mandates.
)[10][11] The results of the election were initially inconclusive, but the Socialists and their allies eventually formed a new coalition government with the For a European Serbia alliance.
[12] Serbia's electoral system was reformed in 2011, such that parliamentary mandates were awarded in numerical order to candidates on successful lists.
Čolaković was re-elected to the assembly in the elections of 2012 and 2014, in each case after receiving the eleventh position on the Socialist list (which won forty-four mandates each time).