Hamilton will join the team next month and believes that although the team currently is a way off the pace, they have long term potential.
"It looks like in Brazil Mercedes were 1.1 seconds behind, so we have got a long, long, steep curve to climb, but I don't think that's impossible", the 2008 world champion told Sky Sports News.
"I think the guys have great potential and that's why I'm going there. I don't see it as a short-term thing."
Hamilton believes that it could be until mid-2013 when his influence starts to improve performance.
""I don't get in the car until February so I won't be able to have a big enough impact until at least six months down the line. I really think 2014 has to be the most important year, or the most competitive year. But I don't see why we can't try and clinch a few podiums. If we can get some wins next year - if it just happens to go really, really well - then we will be smiling, but we'll see."
Hamilton also thinks that McLaren's MP4-28 will be a contender for both championships.
"I feel positive about their car next year. The car already from this year was pretty awesome and next year is an evolution of this car. I think next year they are going to have a championship contender, for sure."