Nikolić received the eighty-first position on the Progressive Party's Serbia Is Winning electoral list in the 2016 Serbian parliamentary election and was elected when the list won a majority victory with 131 out of 250 mandates.[2] In the parliament that followed, she was a member of the environmental protection committee, a deputy member of the spatial planning committee[a] and the European integration committee, and a member of the parliamentary friendship groups with Austria, Azerbaijan, Belarus, Bolivia, China, France, Georgia, Germany, Kazakhstan, Morocco, Russia, Slovenia, Sweden, and Switzerland.[3]
She was promoted to the eighth position on the Progressive Party's list in the 2020 parliamentary election and was re-elected when the list won a landslide majority with 188 mandates.[4] In her second term, she was a member of the administrative committee[b] and the spatial planning committee, a deputy member of the committee on human and minority rights and gender equality, a member of Serbia's delegation to the Parliamentary Assembly of the Mediterranean, the head of Serbia's parliamentary friendship group with Ghana, and a member of fifty-two other friendship groups.[c][5]
Nikolić was given the thirty-sixth position on the SNS's list in the 2022 parliamentary election and was elected to a third term when the list won a plurality victory with 120 mandates.[6] She again served on the spatial planning committee and was a deputy member of the committee on the diaspora and Serbs in the region, a deputy member of Serbia's delegation to the Parliamentary Assembly of the Mediterranean, the leader of Serbia's parliamentary friendship group with the Democratic Republic of the Congo, and a member of fifty-seven other friendship groups.[d][7]
In the 2023 parliamentary election, she appeared in the thirty-second position on the SNS's Serbia Must Not Stop list and was again re-elected when the list won 129 seats.[8] In her fourth term, she was a deputy member of the stabilization and association committee.[9]
She resigned from the national assembly on 10 June 2024, as she could not hold a dual mandate as a legislator and a member of the executive branch of government in Ub.[10]
Nikolić received the fifth position on the Progressive Party's electoral list for the Ub municipal assembly in the 2020 Serbian local elections and was elected when the list won twenty-six out of thirty mandates.[11][12] She was chosen as speaker of the assembly after the election.[13]
The Ub municipal assembly was dissolved for early elections in October 2023, and Nikolić was appointed as a member of a provisional authority that oversaw the municipality pending the creation of a new administration.[14] She again appeared in the fifth position on the SNS's list in the election that followed and was re-elected when the list won twenty-one seats.[15] She was chosen for a second term as speaker when the new assembly convened in early 2024.[16]
Ub mayor Darko Glišić resigned on 10 May 2024 after being appointed as a minister in the Serbian government. His deputy Aleksandar Jovanović Džajić became mayor on 7 June 2024, and Nikolić was appointed as the municipality's new deputy mayor on the same day.[17]