"It's clear from working with them that they are racers," said the 33-year-old Finn, the 2007 world champion with Ferrari who made an impressive comeback last season after two years in rallying.
"You can see in their history that they've won championships. Nothing I saw last year made me think that another championship was impossible," he said of the former Renault and Benetton team.
"The team have beaten everyone before, there's nothing to say they can't do it again."
Raikkonen won the Abu Dhabi Grand Prix last season and finished third overall in the championship with seven podiums.
Team principal Eric Boullier said great things were possible for Lotus, who finished fourth overall last year, with the pairing of Raikkonen and Frenchman Romain Grosjean.
"Our ambitious plan to turn ourselves into one of the top teams in Formula One is coming to fruition and now we need to harness this with strong and regular podium results," he said.
Renault won championships in 2005 and 2006, while predecessors Benetton took drivers' titles with Michael Schumacher in 1994 and 1995.
The original Lotus team, whose name lives on with the current Enstone outfit even if there is no direct connection, won seven constructors' crowns between 1963 and 1978.
- Sports & Recreation
- Eric Boullier