MSVC + MFC......

I have 2 radio buttons and needed to have one selected as a defalt button.
I have a member variable for the radio buttons called m_rAli.
The way I made the first button selected as default was like this:

m_rAli = 0;

Is this the correct way?
If i put 1 it selects the second one, so I know this works,
but is there any problems with this?

Any input is helpful....