The owner of a Queens bridal shop, Rafael Castear, has made his home in New York for the last 40 of his 59 years, but that’s not stopping him from running for a seat in Colombia’s Congress.

He is campaigning in New York and other American cities as well as Venezuela, Spain, and Puerto Rico. He has volunteers promoting him in five more countries with Colombian residents, from Austria to Japan. If he wins the March 12 election, he plans to open offices in Bogota and Queens.

The congressional seat Mr. Castear is seeking, representative from the exterior, was created to give a greater voice to Colombia’s expatriates, estimated to number 4 million. With candidates – and voters – spread around the world, the logistics of the election are complicated: It is a uniquely transnational race in which politicians are competing to show they can best represent the interests of Colombian expatriates.

An adjunct professor at Columbia University’s School of International and Public Affairs, Milena Gomez, called the idea of expatriates electing a representative “an interesting experiment,” but said it also contained implicit challenges due to Colombia’s diverse global community. “How can one person represent the interests of people living in Australia or China?” she said. “It’s an illusion.”

More than a dozen of the 33 candidates will gather this weekend at Columbia University for a forum at which Ms. Gomez will be a moderator. Two of the four New York-area candidates will participate; others will travel from as far as Utah, Venezuela, and Spain to explain why they should represent Colombians who have left their homeland.

For the American candidates, the issues center around finding a solution to the growing population of illegal Colombians, changing immigration laws so that families do not have to wait more than a decade to get visas to move to America, and fostering a free trade zone of the Americas. Candidates from other countries share similar concerns, but the issues are slightly tweaked to national circumstances.

In the previous Colombian elections, the vote was not limited to citizens who are abroad. After an adviser to the singer Shakira, Jairo Martinez, won the seat, critics said it was because of votes from his home region. This time, only those outside Colombia can vote for the seat.

With this move, the South American nation of 42 million has taken to the next level a trend that is sweeping Latin America. While other countries such as the Dominican Republic, Mexico, and Ecuador are just beginning to allow their expatriates to vote from abroad, Colombia’s emigrants have been voting in presidential elections since 1961. For the first time this year, they will also be solely responsible for electing their own representative.

Although the turnout for previous elections has been light – with just over 100,000 Colombians abroad turning out to vote for president – a director of the Immigration Studies Institute at New York University, Marcelo Suarez-Orozco, said this election’s significance should not be underestimated. “The elections will be decided in Colombia, but there may be a margin that is the beginning of an important and influential story,” he said.

More than anything else, what’s generating the interest, he said, is money. He noted that for every million Colombians overseas, about $1 billion in remittances is sent every month. “This is part of a more general pattern, where countries of emigration, countries that are sending large numbers of immigrants to other parts of the world, are claiming them in a systematic way,” Mr. Suarez-Orozco said.

In addition to Mr. Castear, there are two other candidates in New York City, which hosts one of the largest Colombian populations in the nation at about 100,000. One, who practices natural medicine in Jackson Heights, Jairo Casas, has decorated the yard outside his office with a string of Colombian flags and signs advertising his campaign. Others have staked their territory by taking to the airwaves in debates or placing campaign posters and flyers in restaurants and Colombian-owned businesses. They have staked their territory in Jackson Heights, Queens, the city’s main Colombian neighborhood, putting up flags and campaign posters in restaurants.

Mr. Castear, who is an American citizen, plans to spend $40,000 to $50,000 on his election. To foster a universal appeal in a diverse community, he is running on a platform heralding that while he may seem “more ‘gringo’ than Colombian,” his dual allegiances, including consistent support for Colombian organizations, make him the perfect candidate.

“I feel proud to be Colombian and to be an American citizen,” Mr. Castear said in Spanish. “We already have dual nationality in the U.S., we want to do this in Spain, Canada, in other countries, so they can feel Columbian but also feel part of where they live.”