This week, Andres Manuel Lopez Obrador has declared himself president, threatened to close roads and airports with mass demonstrations, and accused the nation's electoral board of ignoring the law.
And the week's not over yet.
Sound bites from the 52-year-old leftist and former mayor have kept Mexico's presidential election at the top of the news in advance of a rally Sunday that his supporters say will draw more than a million people to the capital's main square.
Unofficial returns show he lost the July 2 presidential election by less than a percentage point to conservative candidate Felipe Calderon.
Lopez Obrador says that fraud, human error and a government conspiracy swung the election but that a recount would make up the 244,000 votes he's behind. The Federal Electoral Tribunal is considering the candidate's 836-page appeal and has until Sept. 6 to declare a winner. So far, there is proof of only scattered arithmetic mistakes.
Lopez Obrador is looking to Sunday's rally -- his third since the election -- as flesh-and-blood evidence that Mexicans believe his accusations more than claims by Calderon and the government that the election was clean.
"I am the president of Mexico," he told U.S.-based Univision on Wednesday. "I am absolutely certain we won the presidential election," he said on Mexico's Televisa network.
On Monday, he filed a lawsuit alleging the board of the Federal Electoral Institute failed to keep business interests from funding last-minute attack ads against him. "They don't act according to the law," he told the Associated Press on Thursday.
Whether or not he is granted a recount -- and most believe it won't happen -- Lopez Obrador appears determined to go down swinging.
"He's leading a postelection struggle that in embryonic form could be a broad social movement," said Daniel Lund, a Mexico City-based analyst. "He's not Gandhi, but he's Lopez Obrador."
The candidate has earned a reputation for his deft use of civil disobedience. A little more than a year ago, he beat back efforts by Congress and President Vicente Fox to have him disqualified as a presidential candidate. Millions marched on his behalf.
Lopez Obrador then led a presidential campaign that promised to help Mexico's poor, who make up half the population, and end the privileges of the wealthy.
He had a big lead in the spring, but it was eroded. For a time he refused to give interviews and ignored attack ads by Calderon. However, he finished the campaign with a slight edge in most polls.
On election night, he and Calderon both said they had won, and the tug-of-war has gone on since.
Calderon is filling the role of president-elect, meeting with interest groups and fielding congratulatory phone calls from heads of state. He opposes a recount on legal grounds, saying ballot boxes can be opened only with evidence of a miscount at individual polling stations.
"One shouldn't deceive anyone with suspicions," Calderon said Thursday. "No one in Mexico can place themselves over the law and institutions."
A recount could have one of several outcomes: Calderon could be the winner by a comfortable margin, or he could be declared the winner amid findings of errors or cheating. Or he could lose.
The Federal Electoral Institute is running what can be described as defensive TV and radio ads congratulating Mexicans for holding a fair election.
And Fox said Thursday that people -- he didn't name names -- need to respect Mexico's laws and institutions.
Exit polls by Consulta Mitofsky showed that Lopez Obrador voters overwhelmingly disapprove of Fox, who, like Calderon, champions the free-market economy.
Lopez Obrador, meanwhile, has threatened to send his people to the streets beyond the central square, the Zocalo. After all, he told Televisa on Wednesday, Fox supporters blocked highways and seized an airport after Fox lost a 1991 governor's race in a disputed election.
"The current president felt he was robbed back then and he called for civil resistance and the seizure of highways and an airport," Lopez Obrador told the Televisa interviewer.
Now, he said, some people thought he should just file a complaint and say, "That's fine, I'm going home.' "
Carlos Martinez and Cecilia Sanchez of The Times' Mexico City Bureau contributed to this report.