Story highlights "We are regaining our lost dignity," Tsipras tells cheering supporters:

Official projections indicate the left-wing Syriza party has won at least 149 seats in Parliament

The party has vowed to renegotiate Greece's bailout and get some of its debt written off

(CNN) The firebrand leader of Greece's left-wing Syriza party appeared to be bracing for a bigger battle as he declared victory in Sunday's election.

Now that his party has apparently won the support of his country's voters, Alexis Tsipras has another fight in front of him: making good on his campaign promise to renegotiate the terms of Greece's bailout.

"We are regaining our lost dignity ... Now that we are heard by all of Europe, we will fight with the same passion, the same confidence," Tsipras told cheering supporters. "So let's go and let's all continue this beautiful and tough fight."

With more than 70% of votes counted, Syriza was officially projected to win at least 149 seats in the 300-seat Parliament.

Exit polls also placed the party in the lead. But analysts cautioned that it was still too close to call whether Syriza would win a majority of seats -- a key step that would allow the party to govern without forming a coalition government.

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