(CNN) For its advocates, bullfighting is an indelible part of Spanish culture, a ritual that forms part of the nation's cultural patrimony, immortalized in countless works of art.

Both professional bullfights and bull running events remain popular in Spain, especially in the summertime.

However the sport has become increasingly politicized in recent years, and recent developments in the southern region of Andalucia have underlined bullfighting's new-found importance as a political symbol.

In December, Vox, a far-right party known for its hard line stance on illegal immigration, won 12 seats in a regional election for the first time since the death of dictator Francisco Franco in 1975.

This week, Vox used its position as kingmaker to join a center-right coalition after making a deal with the Partido Popular.

Santiago Abascal, leader of Spain's far-right party VOX

In return for its support, Vox negotiated a number of conditions with the PP, including commitments to lower taxes, combat illegal immigration, and tackle Islamic fundamentalism.

Another intriguing addition to the list was "support for our traditions, hunting and bullfighting."

At the same time, on the other side of the political divide, certain sectors of the Spanish left have been working in conjunction with animal rights campaigners to have the tradition banned.

However this politicization is fairly recent, said Beatriz Badorrey Martín, author of Another History of Bullfighting: Bulls, Law and Society (1235-1854) and a lecturer at Spain's Universidad Nacional de Educación a Distancia (UNED), in a phone interview with CNN.

"Politically it has never had a color," said Badorrey Martín, a self-confessed fan of bullfighting. "Historically it has been part of life for all social classes."

During the Spanish Civil War (1936-39), both right-wingers and left-wingers organized bullfights as a way of raising funds, said Badorrey Martín, who emphasized that her academic research focuses on the earlier history of the sport.

Spanish matador Ivan Fandino performs during a bullfight.

Fast forward a few decades, however, and the discourse around bullfighting is markedly different at the political extremes.

For the Fundación Toro de Lidia, an NGO that promotes bullfighting in Spain, taking a strong position for or against bullfighting is part of a political strategy for extreme left parties that have grown in strength in the last few years, as well as their electoral opponents.

"Recently political parties at the other extreme of the political spectrum have seen in bullfighting an opportunity to position themselves in the center of the debate," a spokesperson told CNN via email, "at the same time displaying themselves as guarantors of the unity of the Spanish nation through the defense of something as symbolic as bullfighting."

Vox supporters celebrate election results in Andalucia.

The "defense" of bullfighting might have become a newly important political debate in recent times, but anti-bullfighting campaigners have previously won some important victories.

In 2013, Catalonia became the second autonomous region in Spain to ban the sport, two decades after the Canary Islands.

Their campaigns continue in other parts of Spain, and there are various explanations for their growing success.

For author Badorrey Martín, city dwellers are disconnected from the realities of rural life, which forms the backbone of bullfighting culture.

At the Fundacíon Toro de Lidia, it is thought that attitudes have been affected by the international animal rights movement, which has succeeded in changing the way we see our relationship with animals.

"Bullfighting is seen with increasing apprehension by a growing number of people, who previously were simply indifferent to the cultural expression of the bulls," wrote a spokesperson.

Whether bullfighting inspires strong feelings or not, there is no denying that the sport has become a lightning rod for political debate in Spain.

However other political parties in Spain are more worried about a proposal to deport 52,000 "illegal immigrants" and other right-wing policies which also feature in the Vox-PP agreement.

"It's an agreement between right-wing forces and the extreme right, which is being sanitized," wrote a spokesperson for the Partido Socialista Obrero Español, which had been in power in Andalucia for 36 years until the December elections.

However Pablo Casado, leader of the Partido Popular, said in a statement that the agreement shows his party is the "only one that is in the center and can reach a compromise with both left and right."

While Spain is not scheduled to hold a general election until 2020, there will be a number of regional and local elections this year. Polls show that the far-right could repeat its success in Andalucia and pick up seats in other areas of the country, according to Reuters.