“Through my years of hacking, I realized the problem wasn’t so much the politics, but the politicians,” Mr. Markun said in an interview at LabHacker, a digital laboratory he opened in São Paulo. “And the only way to bring politics closer to the people is to bring common people into politics.”

Experts say it is unlikely there will be a big shift in the political landscape in October, but the new candidates could lay the groundwork for greater success in future elections.

“It’s a very steep climb,” said Monica de Bolle, a Brazil expert at the Peterson Institute for International Economics. “There is a good possibility that a small group of candidates will make it. If they stay on message, there will be more chance for renewal in the future.”

Another outsider candidate, Michelle Guimaraes, a former executive at Johnson & Johnson, said she was drawn to politics by the poor health services in her native state of Amazonas and the meager representation of women in elected office in Brazil.

“I decided it was time for the same politicians who’ve been in power for the last 30 years to retire,” said Ms. Guimaraes, who is running for the lower house of Congress, where women hold less than 10 percent of seats. “And that meant people like me would have to get involved.”

She may get a lift from a recent decision from the Supreme Electoral Court that ordered parties to devote at least 30 percent of public campaign funds and federally mandated airtime to female candidates.