Republican presidential candidate Ben Carson said he’d consider a top-three finish in next week’s Iowa caucuses a success, as current polls show him running fourth behind leaders Donald Trump and Ted Cruz, as well as Marco Rubio.

Carson suggested he would reassess his campaign if he falls out of the top three in Iowa, as polls in New Hampshire, another early-voting state, also show him trailing.

“I obviously would like to finish in the top three,” Carson said in Des Moines.“There’s always a path, but you know, you always have to look at the trends, you have to look at what is happening, what are people saying.”

Candidates from both parties are crisscrossing Iowa, which will hold the first votes of the 2016 election on Monday.

Carson, the one-time Iowa front-runner, has slumped in the polls since October. This week, a Quinnipiac survey showed Carson in fourth place, with 7 percent support. His campaign has also had to endure a major staff shake-up, as his campaign manager, communications director and policy director quit simultaneously in late December. His finance chair also resigned earlier this month. Carson said the decision to change his staff came after a “deep dive” into his campaign infrastructure.

“When you start an organization from scratch, you have to trust people to some degree,” he said. “You have to assume they all know what they’re doing and that they are all fiscally responsible. As time goes on and you discover that maybe that isn’t the case, you make corrections.”