Ecuador's Correa gains momentum before vote-polls

QUITO, Aug 19 (Reuters) - Support for Ecuadorean leftist President Rafael Correa continues to grow before a referendum to approve a new constitution that would expand his authority in the OPEC nation, polls showed on Tuesday.

Independent pollster Santiago Perez said his poll released late on Monday showed that backing for the new constitution rose to 50 percent, close to the majority needed for approval. Opposition to the new constitution hovered around 27 percent.

Correa, an ex-college professor, is popular among Ecuadoreans for his heavy spending on the poor and his pledges to battle a political old guard he blames for the instability that helped oust his three predecessors.

The new constitution would give Correa more sway over the legislature and top courts, and allow him to run for re-election once more.

Critics of the former economy minister and ally of Venezuelan President Hugo Chavez say he wants to build up autocratic powers.

In another survey released on Tuesday, pollster CMS showed support for the constitution increased 4 points from the last poll to 43 percent. CMS carried out a telephone survey of 21,943 people.

"Even after his clashes with the church and political parties, Correa still has a very high credibility," CMS's head pollster, Santiago Cuesta, told a local television station, adding that 24 percent of voters oppose the new constitution.

Church leaders say the new constitution could pave the way for abortion and gay marriage, which Correa denies. Pollsters say the feud could cost him support in the Sept. 28 referendum.

Both polls showed between 26 percent and 38 percent of voters remain undecided.