Three left-leaning Polish opposition political parties announced on Tuesday they had approved openly gay politician Robert Biedron to be their presidential candidate in the upcoming May elections. Human rights advocates have supported his entry into the race.

Biedron, 44, has been an activist in Poland for years and has served as a Polish member of Parliament as well as the mayor of the northern city of Slupsk. He currently serves as a member of the European Parliament, a European Union governing body, and as leader Spring, one of Poland’s three leftist parties.

Biedron thanked the alliance of leftist parties via Twitter on Tuesday for their support of his candidacy, saying it was “a great honor.”

“The left proves once again that cooperation works well for us. And we will continue to do so — for the good of Polish women and men,” he wrote.

Dziękuję @__Lewica oraz @partiarazem za poparcie mojej kandydatury w wyborach na urząd Prezydenta RP. To wielki zaszczyt. 🇵🇱✌️



Lewica po raz kolejny udowodnia, że współpraca świetnie nam wychodzi. I będziemy to robić dalej - dla dobra Polek i Polaków. pic.twitter.com/z8jOi5zk1e — Robert Biedroń (@RobertBiedron) January 7, 2020

In May, Biedron will face the current president, Andrzej Duda, of the right-wing Law and Justice party and the liberal candidate Malgorzata Kidawa-Blonska.

The ruling Law and Justice party has recently made headlines for targeting LGBTQ rights in central Europe’s largest country, making Biedron’s candidacy even more noteworthy. And last year, the majority-Catholic nation also made headlines for the Catholic church doubling down on anti-gay rhetoric and the appearance of “LGBT-free Zone” stickers.

In December, the European Parliament condemned the stickers and called on Polish authorities to take more action to protect LGBTQ rights.

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The conservative Polish Gazeta Polska magazine is including "LGBT-free zone" stickers inside its weekly edition amid rising tensions between LGBT activists and a conservative Christian movement supported by the country's right-wing ruling party. Jaap Arriens / Sipa USA via AP

Bierdon has “clear views on the secular state, on social affairs, on the E.U., on matters of freedom, including women's issues," said Wlodzimierz Czarzasty, leader of the Democratic Left Alliance, according to Agence France-Presse.

Biedron has also been vocal about the threats of climate change. He has said he would close Poland’s coal mines by 2035.

Despite the rise of anti-gay sentiment in some corners of Poland, Biedron is a popular figure in the country due to his social and political positions, according to Roberto Kulpa, a sociology professor at Plymouth University in the United Kingdom, whose research has explored sexual politics across Europe and in Poland specifically.

“Biedron was able to capture the social imagination of the people in Slupsk,” Kulpa said, by highlighting inequalities and speaking about social welfare.

Kulpa also noted that Biedron hasn’t personally been the target of much homophobia in the press or by his rivals. Instead, his critics are trying to portray him as too far left.

“Not addressing Biedron as a gay person is a smart choice for them,” Kulpa said referring to the Law and Justice party. As for the “LGBTQ-Free Zone” stickers and other anti-gay rhetoric, Kulpa said the ruling party and right-wing politicians were “addressing that kind of invisible, unknown figure of the homosexual.”

“It is a better political, strategic choice, because the concrete figure of Biedron is quite likable,” he said.

Human rights groups have welcomed Biedron’s entry into the presidential election, noting his previous work as an activist.

“He represents kind of everything that the ruling party is trying to eliminate — women’s rights, LGBT rights, democracy, rule of law and so on,” Hillary Margolis, a senior women’s rights researcher at Human Rights Watch, told NBC News.

Margolis sees Biedron’s run as having the potential to galvanize people, including activists, to become active in formal politics. If he succeeds, it could send a signal to other European countries that have also seen rising populist movements, she said. However, if he’s defeated, it could support those same movements. Other countries, she added, are “paying attention” and “taking cues from what’s going on in Poland.”

Katrin Hugendubel, advocacy director of LGBTQ rights group ILGA-Europe, called the growing attacks against LGBTQ people in Poland “worrying” and said she welcomed Biedron’s entry into the presidential race.

“It is ever more important for a candidate to stand strong against an agenda of hate and ensure that the community and allies in Poland who are coming out increasingly in support of LGBTI people, are also heard in the presidential campaigns and election,” Hugendubel said in a statement shared with NBC News.

LGBTQ activists within Poland have also voiced support for Biedron’s candidacy.

“Robert has always stood firmly not only on LGBT rights but all fundamental rights,” Vyachesval Melnyk, executive director of the Polish LGBTQ rights group Campaign Against Homophobia, said in a statement. “Especially now when there is a huge backlash on LGBT rights in Poland, Robert brings hope to our community.”

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