He was mainly known for his participation in the Dutch version of the talent show Popstars on SBS 6 in its second series (2009–2010) in June 2009 in which he won on 29 January 2010.

Klein worked in construction until his talent was discovered by accident during a gig in a pub in 2005.

After successfully auditioning for the Dutch Popstars in 2009, he went on to win the title, receiving a trophy and a record deal to release his debut single "You Raise Me Up", the winner's song sung by all four finalists.

In May 2010, Klein performed at three sold out concerts at the Amsterdam ArenA with De Toppers.

His debut album Vandaag en morgen (meaning "Today and Tomorrow" in Dutch) was released on 9 July 2010.