Just three months ago, the GERB had won the parliamentary election with a good 26 percent.
Revelations about grievances and corruption practices now put a damper on the country.
Sofia - According to updated forecasts, a neck-and-neck race is emerging in the new parliamentary elections in Bulgaria.
Contrary to initial estimates, two polling institutes saw the populist ITN party of the entertainer Slavi Trifonov with 23.4 to 24 percent of the vote and thus a narrow lead over the party of ex-Prime Minister Boiko Borissow.
Borisov's bourgeois GERB would come to 22.9 to 23.5 percent according to the information.
For the final result, the votes of Bulgarians abroad should be decisive in 68 countries - including Germany and Austria.
According to current forecasts, the socialists (ex-KP) would come to 13.3 to 14.2 percent.
The conservative-liberal-green anti-corruption coalition Democratic Bulgaria DB could also make third place.
Six political forces are likely to move into the parliament in Sofia.
The official final results should only be available within four days.
dpa