All bets are off, however, following the June 28 ouster of Mr. Zelaya.
Mr. Santos is now trailing in the race and has been pelted with insults, eggs, and bags of water by Zelaya supporters who think that Santos helped plot Zelaya's forced exile nearly two months ago.
In one incident earlier this month at the National Autonomous University, Santos's bodyguards drew their weapons, beat one student with a pistol butt, and fired one shot in the air as Santos escaped a jeering mob.
No evidence has emerged to substantiate claims that Santos supported the Zelaya's removal. But his nuanced position on Zelaya's ouster and their rivalry within the Liberal Party — Santos served as Zelaya's vice president before breaking with him when he resigned last year to run for president — have made him a ready target.
"This might be the most violent election in the history of the country," said Edmundo Orellana, a long-time Liberal Party stalwart who was Zelaya's defense minister. "There's a lot of anger and hate."
Outside pressure builds
The rising campaign tension threatens interim President Roberto Micheletti's efforts to oversee the Nov. 29 presidential and congressional elections and hand over power to the new president on Jan. 27.
This tension also adds to the pressure that Mr. Micheletti faces from the Obama administration and Latin American and European leaders who've warned that they won't accept the election results unless Zelaya returns to power, preferably under a plan brokered by Costa Rican President Oscar Arias.
"They need to embrace it fully," a senior State Department official said by telephone Wednesday. "Countries in the hemisphere clearly want both sides to resolve this."
The political problems began after Zelaya veered left in the middle of his four-year term and embraced the socialist anti-poverty program of Venezuelan President Hugo Chávez, a fierce US critic. Zelaya worsened matters by pushing for a June 28 vote giving Hondurans the chance to say whether they supported calling a special body to rewrite the country's constitution.
Virtually all of Honduras's major institutions lined up against him, saying that the country's current constitution did not permit the vote. They suspected that Zelaya was bent on making changes so he could seek another term as president, as Mr. Chávez and his allies have done.
Zelaya's supporters say any modification of the constitution wouldn't have taken place until after he left office in January.
Why Lobo benefits
The unintended beneficiary of the June ouster has been Porfirio "Pepe" Lobo, the presidential candidate of the more conservative National Party.
Mr. Lobo is a rancher who flirted with Communism as a youth by studying in the Soviet Union before graduating from the University of Miami. He served as president of Congress and then narrowly lost the 2005 presidential election to Zelaya.
An aide said he wouldn't be available for an interview, in keeping with Lobo's strategy of avoiding discussion of the forced exile.
Santos led Lobo by 39 to 35 percent in a February poll for CID Gallup. A CID poll immediately after Zelaya's ouster showed Lobo had pulled into the lead, 31 to 25, with the number of voters who were undecided or supporting another candidate rising from 27 to 44 percent.
"Elvin is a victim of what's happened," said Carlos Denton, the president of CID Gallup. "The Liberal Party is now divided, and he's the man in the middle. You've got one group that supports Mel (Zelaya) which feels like Elvin is not supporting their effort to bring Mel back. The group not supporting Mel feels like Elvin hasn't supported their side either. Both sides are saying, 'Elvin, we want your support.' If they could settle this, he could bounce back."
Santos is a graduate of Lamar University in Texas whose father was Tegucigalpa's mayor and now serves as the Liberal Party's president. His wife, Becky, won a local beauty pageant 20 years ago, and his supporters frequently say that her beauty is a campaign asset.
Santos agreed to an interview with McClatchy but then didn't make himself available.
He's said that the June 28 vote was illegal but has criticized the military for spiriting Zelaya out of the country that day.
"Zelaya should have had the right to defend himself in the country," said Bill Santos, a cousin and Elvin Santos' campaign manager. Bill Santos noted that Elvin supports the Arias Plan, which, reflecting his centrist position, puts him at odds with the country's interim government.
Victim of outside agitators?
Bill Santos blamed outside agitators for stirring up trouble for his cousin but said onetime supporters would return to the fold once they better understand Elvin Santos' views.
In the meantime, Santos is facing furious Zelaya supporters practically wherever he goes. In the city of La Esperanza in the state of Intibuca last week, Santos held an unannounced meeting with local supporters. Some 100 Zelaya backers found out and chanted "Get out! "Get out!"
When Santos' caravan emerged, they threw bags of water and eggs at the vehicles. "He had better not return to Intibuca," said Gustavo Caceres, one of the protesters. "The response will be even more forceful next time."
Santos canceled a planned campaign stop in the neighboring state of Lempira on Friday.
"We were waiting for him with sticks and stones," said Jose Rosa Sanchez, a local activist. "We wanted to show that we repudiate him."
On Saturday in La Ceiba, a city on the northern coast, pro-Zelaya activists invaded a Santos campaign meeting without the candidate. The hotel where it was taking place cut off electricity to force everyone outside, and police came to keep the two sides apart.
"If the police hadn't come, a fight would have broken out between the two Liberal Party groups," said Geovany Alfonso, the owner of a TV station in La Ceiba.
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