Though a Masters Program adds up to your chances, Its not just the type of degree that decides it. There are alot of other elements such as:
1. Your previous academic record
2. Your work experience (if any)
3. The Masters program you have been admitted in and its relevance to your previous academic record and work expereince.
4. Total expenses and the funds available against it
5. The time when you are applying (Visa Office have a minimum processing time) etc.
And these are just some of the factors which I have understood, specially from this forum.
I have applied for a Masters course and am just waiting for the original letter from the university to arrive so that I can submit my visa. I have to join the University in Januray - 2012.