In 1982, in the first election of the Worker's Party (Partido do Trabalhador), Déda was nominated as a candidate for state representative.

During the three months of the campaign, Déda began to jump in the polls, winning the election still in the first round, with 52.80% of the valid votes, beside the then vice-mayor Edvaldo Nogueira.

In historic victory, which symbolized a change in the political landscape of Sergipe, Marcelo Déda was elected governor, with 52.48% of the vote, next to the vice-governor Belivaldo Chagas also simãodiense.

At the time, still in his twenties, he challenged the policy of Sergipe strong names such as Baker and Jackson Gilton Garcia.

In the city of Aracaju, revitalized throughout the city, he built and renovated many health agencies, created two new hospitals, built several new avenues, the neighborhood Santa Maria (formerly Terra Dura) and planned the construction of the new bridge the day, a great work integration of several neighborhoods in Aracaju, and transformed the Cashew Forro in June festivities, as one of the largest in the country.

During his administration, Aracaju, the capital was considered the best quality of life of the country, surpassing even Curitiba, which had until then, the title of best city in Brazil with Brasília.

Allied to Mr Baker and the Senator Jackson Valadares (PSB), countryman and friend, Marcelo Déda supported the reelection of the successor in the Municipality of Aracaju, Edvaldo Nogueira (PC do B), and emerged victorious in the election during the first round, choosing also more than 60 mayors of the 75 possible throughout the state, proving to be a master political strategist, and the big favorite to win the state government in 2010, with rates that exceeded 70% in early research and towns in the state.