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By Neil Marks
GEORGETOWN, May 11 (Reuters) - Guyana's ruling party could lose its 23-year grip on power in Monday's election where it faces an unprecedented challenge from an opposition coalition seeking to punish the government over corruption claims and break traditionally race-based politics.
Since gaining independence from Britain in 1966, the South American country of 740,000 people has suffered tensions between citizens of Indian and African descent.
The People's Progressive Party/Civic (PPP/C), dominated by the largest Indo-Guyanese ethnic group, has ruled since 1992 and Afro-Guyanese complain they are marginalized.
But a multiracial opposition coalition, a recent fusion between the traditional black party and a smaller third party, seeks to break that hegemony, cheered on by youth less hung up on ethnicity and increasingly fed up with the status quo.
Voters are choosing between the parties of Indo-Guyanese President Donald Ramotar and the opposition coalition's David Granger, an Afro-Guyanese former army brigadier.
Results were expected on Wednesday at the earliest.
"The choices will be between electing a multi-party, inclusionary partnership or perpetuating the PPP's one party dictatorship," said Granger, 69, a historian and publisher.
Ramotar has been accused of authoritarianism for suspending parliament last November to avoid a no-confidence vote.
Hit by corruption claims over relatives and infrastructure projects, as well as party defections, Ramotar denies malfeasance and vows to clean up government if re-elected.
Opponents accuse his party of reverting to scare tactics by drawing parallels between Granger and his Afro-Guyanese People's National Congress (PNC) party's 1964-1992 rule, which was marked by violence, and spooking voters about Granger's military background.
"We saw it happen in Egypt where the military people took off their uniform and put on business suits and then they take over the government and they are shooting people everywhere," said Ramotar, 64.
Gold, diamond, and bauxite have boosted growth in recent years, but many Guyanese have yet to enjoy the spoils.
"Vengeful politics have not served us well and this is the time to close the curtains and move forward as one nation in unity," said Frank White, 33, an aspiring entrepreneur, who voted for the opposition coalition.
Other voters were staying loyal to Ramotar.
"I have lived and witnessed a nation that has developed significantly, one that has leapfrogged from bankrupt to progressing. We are way better off than we have ever been," said Amanda Tiwari, 31, who backs the PPP. (Writing by Alexandra Ulmer; Editing by Andrew Cawthorne, W Simon and Richard Chang)