A retired army general is poised to become Guyana's new president after a multi-ethnic opposition coalition defeated a party that has been in power for nearly 25 years, officials said Thursday.

Preliminary results show that David Arthur Granger and his Partnership for National Unity-Alliance for Change Coalition obtained nearly 207,000 votes in Monday's general elections. The governing People's Progressive Party obtained almost 201,500 votes, according to chief elections officer Keith Lowenfield.

The coalition is expected to have a three- or four-seat majority in the 65-member Parliament of the South American country. It previously had a one-seat majority and often clashed with President Donald Ramotar, who forced early elections after suspending and dissolving Parliament to avoid a no-confidence vote.

Ramotar's party has been in power since 1992 and was seeking a sixth consecutive term while facing accusations of corruption and mismanagement. It has long received support mostly from Guyanese of Indian descent. The party had requested a partial recount of ballots, but the U.S. Embassy said that allegations about irregularities were unfounded, calling the election "free and fair."

Officials said 69-year-old Granger could be sworn in late Thursday or early Friday, becoming Guyana's eighth government leader since the country gained independence from Britain in 1966. He has promised to end racial politics that have long defined Guyana, a country of nearly 746,000 people who are mainly of Indian and African descent.

"The time has come for racial and national unity," Granger had said ahead of the elections. "The time has come to end winner-take-all politics, corruption, nepotism and the squandering of our resources."

Ramotar had previously defeated Granger and another coalition in 2011.

Granger is the son of a police officer and studied at a military school in the United Kingdom in the 1960s before returning to serve in Guyana's military. He retired in the late 1980s as a one-star general and later served as a government security adviser. He is also a well-known historian.

Granger will oversee a country whose economy relies heavily on commodities including gold, sugar, bauxite and rice.