David D. Kirkpatrick CAIRO — Hamdeen Sabahi was the most popular leader in the fight against Egypt's new Islamist-backed constitution. Now he is preparing for his next battle: against Islamist leaders' plans for Western-style free-market reforms. Do not listen to your allies in the Muslim Brotherhood, Sabahi said he warned President Mohammed Morsi, of the Brotherhood's political arm, in a private meeting a few weeks ago. “Because the Brotherhood's economic and social thought is the same as Mubarak's: the law of the markets,” Sabahi said he had told Morsi, referring to Hosni Mubarak, the former president. “You will just make the poor poorer, and they will be angry with you just as they were with Mubarak.” Sabahi, 58, a leftist in the style of another former president, Gamal Abdel Nasser, frightens most economists. He is an outspoken opponent of free-market economic moves in general as well as of a pending $4.5 billion loan from the International Monetary Fund that economists say is urgently needed to avert a catastrophic currency collapse. But to the dismay of some Western diplomats, Sabahi is emerging as an increasingly salient voice in Egyptian politics, in part because of the bruising race to ratify the Islamist-backed charter. Both sides now expect the anti-Islamist opposition to reap big gains in the coming parliamentary vote, set to be held in two months against the backdrop of a simultaneous debate over the IMF loan. Among Egypt's opposition figures, Sabahi has the biggest base of support in the streets. After campaigning as a dark horse in the spring's presidential election, he missed the runoff by fewer than a million votes, finishing the first round almost neck and neck with Morsi. Economic overhaul now poses a critical test of Egypt's fragile democracy. Without enough trust in government, the changes to the systems of taxes or subsidies needed to reduce the deficit could easily stir new unrest in the streets, just as such moves have in the past. “Why support him, for what?” Sabahi said in an interview in the borrowed offices of an Egyptian film director, decorated with pictures of President Nasser but also of Che Guevara. “Is he a democratic ruler, is he a revolutionary?” — NYT