(For more on Ecuador's election, click on [nN26486483])

* Results give Correa more than 50 percent of vote

* Correa party close to absolute majority in assembly

* Tough economic challenges in volatile country (Recasts with new Correa comments)

By Alonso Soto and Frank Jack Daniel

QUITO, April 27 (Reuters) - President Rafael Correa vowed to radicalize his "revolution" after a re-election victory made him Ecuador's most powerful leader since it adopted democracy, but he must first deal with shrunken oil revenues and a weak economy.

The left-wing Correa won 52 percent of the vote, with a 24 percentage point lead over his nearest rival, former President Lucio Gutierrez, according to official results based on returns from 70 percent of polling stations.

Correa's party was close to securing an absolute majority in the 124-member assembly, exit polls showed, making it easier for him to pass his proposals to limit the power of media companies and increase regulation of banks and the armed forces.

He quickly vowed to steer his OPEC country on a path toward what he calls "21st Century Socialism" [N26472915] after the first re-election in the 30-year-old democracy of Ecuador, where the last three elected presidents were toppled by unrest.