BUENOS AIRES (Reuters) - Argentina s ruling party candidate for Senate in the key  province of Buenos Aires is 4.8 percentage points ahead of the opposition candidate, according to a poll by consultancy Management & Fit sent exclusively to Reuters on Friday. The country s mid-term congressional election will be held this Sunday, and is seen as an early indicator of the electoral power that President Mauricio Macri will have going into his 2019 re-election campaign.  Esteban Bullrich, of Macri s  Cambiemos  or  Let s Change  party, is forecast to win 35.3 percent of votes in his bid for the Senate, according to the poll. Buenos Aires province is home to a third of Argentina s population. His opponent, former President Cristina Fernandez, has 30.5 percent of voter intentions, according to the Management & Fit survey of 2,000 voters. The poll had a margin of error of 3.3 to 3.5 percentage points.  Fernandez is loved by many low-income Argentines for her generous social spending. Macri, a proponent of free-markets,  and Cambiemos have been criticized for reducing popular home heating and transportation subsidies but lauded by investors who say the President s policies can return Argentina to sustained growth. 
Official candidate seen ahead in Buenos Aires Senate race: poll