Thousands hit the streets to welcome Venezuelan President Hugo Chávez home following a three-week absence during which a cancerous tumor was removed.

Wearing the combat fatigues and red beret of his army days, Chávez projected strength as he spoke from the balcony of the presidential palace on Monday, waving to the crowd below and raising a fist. 

He vowed to beat cancer after undergoing surgery in Cuba.

"We will also win this battle for life," Chávez said. "We will live! We will be victorious!" Nonetheless, signs of Chávez's fragile health peeked through the stagecraft.

At one point, the 56-year-old leader grimaced with apparent discomfort as he struggled to wave his country's yellow, blue and red flag above his head. The flag ended up awkwardly draping over his scalp, until Chávez emerged with an embarrassed smile from the fabric.

About 30 minutes into the speech, one of his daughters stepped up to remind him of doctors' orders that he not strain himself by speaking at his normal, marathon length.

"I shouldn't be here for too long," Chávez said. "This recovery process has to be carefully watched to the extreme."

His surprise return in the wee hours of Monday morning was signature Chávez and sent a message that he remains in control. While he was away for nearly a month in Cuba, uncertainty swirled in Venezuela, both about how sick he is and what would happen if cancer were to force him from power.

"Beloved Venezuelan people, I'm sure you understand perfectly the difficulties of this battle," Chávez told the mass of supporters. "No one should believe that my presence here... means that we've won the battle."

The long-term political impact of cancer for a leader who thrives on the spotlight remain unclear. But Chávez will likely play up his plight to rally his movement as he looks ahead to 2012 elections, in which he'll seek to extend his nearly 13-year-old administration. His allies say they are convinced he will still be their candidate.

Unanswered questions about Chávez's health continue to abound, despite the details he offered in Monday's speech. He told the multitude he underwent surgery in Cuba on June 20 to remove a cancerous tumor, which his foreign minister said was extracted from the same part of the "pelvic region" where Chávez had an abscess removed nine days earlier.

Chávez hasn't said what type of cancer is involved nor whether he is receiving chemotherapy, radiation or other treatments. Based on Chávez's account, medical experts said it's most likely he has colorectal cancer, but Chávez hasn't confirmed that.

Chávez's opponents have criticized the lack of details about his illness.

"We don't know exactly what the president's illness is, what treatment he needs and what consequences this treatment will bring," opposition lawmaker Alfonso Marquina told The Associated Press. "What we demand is greater responsibility, not only on the president's part but by all of those high in the government to inform the Venezuelan people properly about the president's real situation."

Chávez has been dominant in the oil-exporting country for the nearly 13 years he's spent in office, and his absence created a void that he clearly wanted to fill.

Jaua, Foreign Minister Nicolas Maduro and other confidants have stepped up their appearances in Chávez's absence, insisting they remain unified.

With his return, Chávez has the potential to fill that gap, but political observers will be watching closely to see how often he appears in public, whether he has the stamina to keep up a full schedule, and whether he might be quietly making plans to throw his support behind any of his allies as potential heirs.

Adam Isacson, an analyst at the Washington Office on Latin America, a think tank, said Chávez should enjoy a boost for now.

"Hugo Chávez's illness will generate a lot of sympathy for him," Isacson said. "It is already moving Venezuela's political debate away from themes that don't work to the president's advantage, like crime, power shortages, the economy, and concentration of power in the presidency."

"On the other hand, it also moves the debate in directions that Chávez would not want to see it go," Isacson said. "For the first time in years, Venezuelans are thinking about what a post-Chávez era might look like. This raises concerns about the lack of an heir-apparent."

Chávez seemed determined to dispel such doubts.

Looking down on his supporters outside the palace, Chávez gushed: "My thanks for so much support, so many manifestations of love."

"Love is the best remedy for any illness," he said.

Based on reporting by The Associated Press.

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