Blending/Fading Camera & Pixel Shader 1.1

For my current project, I'll need to be able to fade smoothly between two different cameras, or impose one camera's display over the primary camera using alpha blending. After researching it, it looks like the easiest way to do this is to apply a shader to the camera's output using a full screen effect with OnRenderImage to fade out the camera's image. My understanding though is that utilizing render-textures in this fashion will require pixel shader 2.0 as a minimum requirement. It's come up as a concern that our target audience may not have devices that support it.

So my question is, is there a way to alpha blend the output of a second camera over the main output without relying on shader 2.0? I've had a hard time finding information on what you can and can't do with different shader versions, and no easy way to tell what your programs requirements currently are.