Uribe popularity dips due to scandal in Colombia

* Agricultural subsidy scandal hurts government's image

* Fewer Colombians say they want Uribe to run again

BOGOTA, Nov 6 (Reuters) - A scandal involving accusations of improper state payouts to friends of Colombian President Alvaro Uribe has cut his popularity and threatens to complicate his re-election plans, according to a poll released on Friday.

Uribe's popularity dropped to 64 percent from 70 percent two months ago, said the Invamer-Gallup survey.

Washington's ally in the left-tilting Andean region, Uribe may run for a third term if the subsidy scandal and sluggish economy do not bog down efforts by his supporters to change the constitution to allow him to stand in next May's election.

The conservative leader remains the most popular politician in the country thanks to his U.S.-backed crackdown on drug-running Marxist guerrillas who are widely loathed for their practice of kidnapping.

But the scandal -- in which the opposition accuses the agriculture ministry of handing out millions of dollars in subsidies to businesses and individuals, including a local beauty queen, with ties to Uribe -- has taken a toll.

"It has affected the perception of the government's handling of corruption," said Jorge Londono, head of Invamer-Gallup, which carried out the survey of 1,000 voters in the cities of Bogota, Medellin, Cali and Barranquilla.

Adding to Uribe's troubles, Colombia has been pushed into recession by fallout from the world economic slowdown.

"This is the lowest popularity rating we've ever seen for Uribe," Londono said. "When there is a scandal at a time of slow economic activity, it hurts."

The government denies doing anything illegal in the scandal, which includes a Caribbean coast beauty queen was given an agricultural subsidy despite owning no land.

The opposition is trying to have Agriculture Minister Andres Fernandez fired over the subsidies, saying that payments were weighted toward people who contributed to Uribe's campaigns and supported a constitutional amendment that allowed the president to run for and win a second term in 2006.

The poll, which had a margin of error of 3 percent, also showed a softening of support for Uribe's 2010 re-election effort. Fifty-two percent, down from 58 percent in Invamer-Gallup's previous poll two months ago, said they support a referendum to allow him to run again next year.

Uribe says he wants his investor-friendly economic policies and his tough stance on security to continue. But he has not said if he supports an effort by his supporters to amend the constitution to allow him to seek office again next year.

Congress has passed a bill calling for a referendum to ask voters if they want another change in law clearing the way for a 2010 Uribe campaign. The bill is under review by the courts.

Editing by Paul Simao