As long as the speaker cables are wired the same, the effect would be the same as using one heavier gauge cable. One additional benefit would be lowered contact resistance, since you'd be making two contacts instead of one. Now, would you hear the difference? I doubt it, but maybe. If you try it, though, be careful. If the cables are not wired the same, you'll short the amplifier's output, and that could destroy the amp.
To answer your specific question, no, the amp would not be running into 2 ohms.