La Paz, October 10 (RHC-Xinhua) -- Bolivian President Evo Morales is widely expected to win a third term in Sunday's general elections, according to opinion polls.

The latest polls show that Morales will get about 59 percent of the vote. His closest rival, millionaire Samuel Doria Medina, is expected to win less than 20 percent.

If re-elected for another five-year term, Morales will become the longest-serving president of Bolivia. Andres de Santa Cruz, one of Bolivia's founding fathers, served for 10 years in 1829.

Coupled with Morales' strong performance, his ruling Movement Toward Socialism party is likely to win a two-thirds majority in the legislature in Sunday's elections.

Morales became president in January 2006. He won a recall referendum that renewed his mandate with 67.41 percent of the vote two years later.

Armed with the vote of confidence, Morales, the first indigenous president in Bolivia's history, introduced a new constitution in 2009 that granted more rights and autonomy to Bolivia's indigenous people. He was re-elected with a landslide in the same year.

The president and his party's popularity is largely due to economic and social policies that have lifted people out of poverty and empowered long marginalized sectors of society.

Credit rating agency Fitch has promoted Bolivia from B- to BB- with a positive outlook. The country's economy is expected to grow more than 5 percent this year following growth of 6.8 percent last year.