Antonescu became Acting President of Romania on 10 July 2012, a few days after President Traian Băsescu was suspended for a second time, and ended his term on 27 August the same year. He continued as President of the Senate until March 2014, after which he slowly withdrew from politics before unsuccessfully returning as the A.Ro candidate in the 2025 presidential election.
Upon graduating in 1985, Crin Antonescu worked as a History teacher in the village of Solești, Vaslui County.[7] He later returned to Tulcea, continuing his teaching activity in Niculițel until 1989.[8] Antonescu worked as a curator for the Tulcea Museum of History and Archaeology from 1989 to 1990, when he resumed his teaching activity at the "Spiru Haret" High School in Tulcea, prior to being elected to the Chamber of Deputies.
Upon joining the National Liberal Party (PNL), Antonescu helped organize the Tulcea branch of the party. In 1995, he was elected PNL Vice President and, subsequently, leader of the liberal politicians active in the Chamber of Deputies, holding that position for two non-consecutive mandates. During his activity in the Chamber of Deputies, he was a member of the Committee for Education, Youth, and Sports, the Foreign Affairs Committee and the Committee of Culture, Arts, and Media.
Antonescu was the Romanian Minister of Youth and Sports from 1997 to 2000.[9] He initiated a series of reforms, the most prominent being the legal perpetuity for Romanian athletes with significant Olympic results.[10]
As of 20 March 2009, Antonescu was the President of the National Liberal Party (PNL), in addition to being the party's candidate for the 2009 presidential elections in Romania. In September 2009, Antonescu was situated third in Romanians' voting preferences for the 2009 Presidential elections.[11][12]
After President Traian Băsescu's suspension on 3 July 2012, he assumed acting Presidency of Romania. After the end of the ad interim term as President of Romania, Antonescu continued to serve as Senate President until the dissolution of USL, after which he resigned from this dignity. After 2014, he slowly but steadily withdrew from politics, resigning from his last remaining political position in late February 2015.[13][14]
Antonescu was selected as the presidential candidate for the 2025 presidential election by the incumbent minority government under the electoral pact Romania Forward Electoral Alliance.[15] Antonescu placed third in the first round of voting on 4 May with 20.34% of the vote.[16]
Antonescu's first wife Aurelia committed suicide in 2004 due to an incurable disease.[17] The two have a daughter, Irina, born in 2001. In June 2009, Antonescu announced he will get married again to party colleague Adina Vălean.[18] The couple got married on 25 September 2009.[19]