SOFIA, April 10 (Reuters) - Bulgaria's main opposition party, GERB, has kept its slight lead over the ruling Socialists just over six weeks before European elections, a poll by Gallup International showed on Wednesday.
The election on May 25 is seen as a key test of the government's long-term survival.
The poll showed support for the centre-right GERB party, led by former Prime Minister Boiko Borisov, edged up to 20.9 percent from 20.7 percent a month ago. Gallup polled 1,013 Bulgarians from March 28 to April 3.
The previous GERB government fell in February 2013 amid protests over high utility bills and corruption.
Backing for the Bulgarian Socialist Party (BSP) rose to 20.0 percent from 19.5 percent in the previous Gallup poll despite its equivocal statements on Russian intervention in Crimea. The Socialists have condemned Russia's actions on the one hand but criticised Bulgaria's involvement in EU sanctions on the other.
A majority of BSP's supporters are pro-Russian and oppose any sanctions on Russia, one of Bulgaria's largest trading partners outside the European Union. The Gallup poll showed 49 percent of all Bulgarians do not support EU sanctions on Russia.
Bulgaria joined the European Union in 2007 and has pushed closer integration with the bloc. But it is almost entirely dependent on Russian energy supplies, forcing it to walk a diplomatic tightrope. It has so far refused to support any widening of sanctions against its former Cold War ally.
Support for the ethnic Turkish MRF party, which is part of Prime Minister Plamen Oresharski's minority coalition, was 6.4 percent.
PARTY Alpha Alpha Gallup Gallup
Research Research When poll conducted March Feb April March GERB 17.5 16.9 20.9 20.7 Socialist party (BSP) 15.2 15.1 20.0 19.5 Movement for Rights and 6.5 6.9 6.4 6.0 Freedom (MRF) Bulgaria without 5.2 5.5 5.3 5.0 Censorship/VMRO Alternative for Bulgarian 4.0 6.1 3.5 3.2 Revival (ABV) Reformist Bloc 5.1 5.0 2.1 3.1 (Reporting by Angel Krasimirov; Editing by Larry King)