The third largest number of votes was for the Golden Dawn, the neo-fascist party, which was polling at 7.3 percent, about 1 percentage point higher than in January’s election.
With over 70% of votes counted, Mr Tsipras held a lead of 35.46%, to the conservative New Democracy Party’s 28.27%.
“Now a solid government ready to deliver is needed quickly”, said European Parliament president Martin Schulz, offering his congratulations.
Over 9.8 million Greeks were registered to vote for a new government which will face the tough task in the next weeks of pushing through the belt-tightening reforms agreed under the three-year bailout accord adopted by parliament last month.
The right-wing Independent Greeks party won ten parliamentary seats.
“In Europe today, Greece and the Greek people are synonymous with resistance and dignity, and this struggle will be continued together for another four years,” Tsipras told his supporters in central Athens.
But probably the biggest loser is Panagiotis Lafazanis, a former Syriza MP who broke away from Tsipras in order to start his own party, Popular Unity.
On the other side of the Greek capital New Democracy voters were less than confident Tsipras will deliver stability and expressed fears that his actions will worsen one of the worst depressions to hit an industrialised country in modern times.
Mr Tsipras says his Syriza party would develop a coalition having the tiny nationalist Independent Greeks (ANEL) party right away.
Tsipras had gambled that by calling an election, he could consolidate his power and rid Syriza of its more radical left elements, who have now split off and are calling for Greece to leave the euro currency zone.
“The new government will now have the mandate to carry out those reforms…”
“On behalf of the European Commission, I would like to congratulate you on the electoral results of last night”, Juncker said in a letter to Tsipras, released to journalists.
It must also oversee a critical bank recapitalization program, without which depositors with more than 100,000 euros ($150,000) in their accounts will be forced to contribute.
He made no specific reference to the 85 billion euro bailout, but Syriza campaigned on a pledge to implement it, while promising also to introduce measures to protect vulnerable groups from some aspects of the deal.
All in all this suggests that the decision is becoming ever more closely balanced with a good chance that we still see rates rise in December.