The wing-back has gone from strength to strength in recent seasons, leading the 2. Bundesliga with 15 assists in Greuther Furth's 2020-21 promotion campaign before adding another 11 in the top flight last term after joining Hoffenheim.
Raum led all Bundesliga defenders in assists, as well as chances created (83) and expected assists (13.9), earning another transfer – this time to Leipzig.
And the Germany defender believes his arrival significantly boosts his new side in their bid to hunt down champions Bayern Munich.
"With the new additions that Bayern has brought in, they are probably clear favourites for the championship," he said.
"But I think we have a team that can also win titles. I want to strengthen this team, and then we'll see how much we can annoy Bayern.
"Of course, the others have strengthened well. But I think the most important transfer was mine to RB Leipzig."
Raum's move comes ahead of the World Cup in Qatar, where the nine-cap Germany international is looking to secure a spot in Hansi Flick's side, and he revealed he spoke to the national team coach about his transfer.
"I was in close contact with national coach Hansi Flick, called him and took him with me on my way," he added.
"He is a coach who always wants to know what is going on in the players' minds, what the next step will be.
"He was immediately convinced of the idea that I fit in well here and can take the next steps. I am firmly convinced that I can assert myself here and hopefully go to the World Cup."