Magneto is someone who can lift Thor's hammer, because he has the power to control metal. The hammer is made out of Mjolnir metal which is still metal.
Another fact is that Thor technically isn't the rightful owner of the hammer. His power can be taken from him by his father Odin. His father gave Thor the hammer, but Odin can take it away any time he wants to.
One more fact is that there is another person on the Avengers team that is worthy to lift Thor's hammer. His name is Steve Rogers (Captain America).
Captain America should be able to anyways. Before he got the serum, he was a small guy from Brooklyn. Who wanted to fight for others, even though he failed, he kept trying and trying and never would stop.
But all in all it would be fun to lift Thor's Hammer