BUENOS AIRES (Reuters) - Argentine President Mauricio Macri is almost certain to run for re-election in 2019, his top campaign adviser said on Thursday, even as he acknowledged that the leader’s market-friendly reforms were unpopular among many poor Argentines.

Jaime Duran Barba, an Ecuadorian who has run campaigns across Latin America and is considered the political guru behind Macri’s surprise win in 2015, told Reuters on Thursday he “did not see a scenario” where Macri was not a candidate.

“The most likely is for Macri to go for re-election, it’s highly probable. But what is certain is that after that he will leave politics,” Duran Barba said in an interview.

Center-right Macri has not said if he will seek re-election and told Reuters in an August interview that he was focused on his current government.

When the time came for Macri to move on, Duran Barba said that there were “important, prepared people” who could dispute the succession. He pointed to city of Buenos Aires mayor Horacio Rodriguez Larreta, Macri’s Cabinet Chief Marcos Pena, and Maria Eugenia Vidal, the governor of Buenos Aires and the most popular politician in Argentina, according to several polls.

But Macri’s “Let’s Change” coalition must first post a strong performance in October’s legislative elections, where one third of the Senate and half of the lower house seats are up for re-election.

“Mauricio’s strategy has always been: in the first two years we can start a transformation, but the point at which we will know if it is possible or not to change Argentina is the mid-term election,” said Duran Barba, who has advised Macri since he first ran for political office in 2003.

The Oct. 22 vote is being closely watched by investors because Macri’s political nemesis and populist two-term predecessor, Cristina Fernandez, is vying for a Senate seat in Buenos Aires province, home to 40 percent of voters. She is believed to be testing the waters for a potential bid for the presidency in 2019.

Fernandez eked out a narrow win over Macri ally Esteban Bullrich in the non-binding primary vote in August, a scenario Duran Barba said was ideal for motivating voters to rally around Bullrich against a divided opposition.

“It was the best option, our numbers always predicted a tie (with Fernandez). I said hopefully she wins by a bit because that way the people will see a need to do something.”

The latest polls, including an internal poll from the Fernandez camp, are showing Bullrich ahead. Macri’s approval ratings are running at 44 percent, according to an Observatorio Electoral survey on Tuesday.

But his reforms have been unpopular with the country’s powerful unions and triggered anti-Macri protests.

Argentina’s economy came out of recession in the second half of last year, later than expected. Duran Barba acknowledged that Macri’s austerity measures had particularly hurt poor slum-dwellers in Buenos Aires province.

“They raised (energy) tariffs, and that was unpopular. We hoped there would be fast results for the economy and that there would be investment. There wasn’t,” Duran Barba said.

He said Fernandez, who has toned down her formerly tub-thumping speeches and gave a rare live interview last week, is copying some of his tactics - such as visits to voters’ homes, ripe for recording and posting on social media.

“Cristina has copied a lot of our way of campaigning,” Barba said. “But it’s hurting her.”

Fernandez’s campaign declined to comment.