However, he began his political trajectory at the age of 28 as a member of the PP, in which he joined in 2005, elected for the first time to the mandate of federal deputy (2007–2011) with 18,886 votes.

In 2014, during the electoral campaign, two of the three polls released by Ibope in Acre pointed to Gladson Cameli's victory.

However, the then-senator-elect did not complete his term in the legislature, being licensed to exercise the post of governor of the state of Acre after the 2018 elections, in which he already won in the first round over candidates Marcus Alexandre (PT), Colonel Ulysses (PSL), Janaína Furtado (Rede) and David Hall (Avante).

Gladson Cameli's victory breaks the existing PT hegemony in the state of Acre for about 20 years.

Gladson also voted in favor of labor reform in July 2017, and stood against Aécio Neves' impeachment on the Senate's ethics board.