By Ricardo Brito

BRASILIA (Reuters) -Former Brazilian President Jair Bolsonaro was staring into the political abyss on Tuesday when a federal electoral court (TSE) justice voted to bar him from office until 2030 for anti-democratic abuse of power during last year's fraught election.

The vote by Benedito Goncalves, the lead justice in the case against Bolsonaro, does not amount to a full conviction, but may set the tone for subsequent judge's votes.

The outlook appears increasingly bleak for Bolsonaro, a career politician who was until recently Brazil's most powerful man. The far-right nationalist narrowly lost Brazil's most troubled election in a generation to his leftist rival Luiz Inacio Lula da Silva, and now faces an institutional reckoning for having forged a nationwide election denial movement.

Bolsonaro stands accused of abusing his power when he summoned ambassadors last year and vented unfounded claims about the security of Brazil's electronic voting system, one of a series of attacks that critics say were aimed at diminishing voters' faith in the vote.

Goncalves said Bolsonaro was guilty of abuse of power and improper use of the media. "Bolsonaro used the meeting with ambassadors to spread doubts, incite conspiracy theories," Goncalves said during his vote.

After his vote, the session was adjourned until Thursday.

Bolsonaro had appeared increasingly sanguine about his hopes of political survival in the lead-up to the vote.

"Everyone seems to say that it's likely I'm going to be barred from office," Bolsonaro told the Folha de S. Paulo newspaper in an interview published this week. "I won't despair. What can I do?"

Yet political ineligibility may not be the end of Bolsonaro's problems. The 68-year-old also faces multiple criminal investigations that could still put him behind bars.

Many of his former allies have turned their backs on him, pinning their hopes on new right-wingers like Sao Paulo Governor Tarcisio Freitas and Minas Gerais Governor Romeu Zema.

Bolsonaro's best hope at relevance may lie with his family, including his wife and lawmaker sons, who could also harbor their own presidential ambitions. He told the Folha de S. Paulo that his wife Michelle could well be a presidential candidate in 2026, but noted she lacked political experience.

(Additional reporting by Carolina Pulice; Editing by Richard Chang and Stephen Coates)