The answer is no. If $\mathbb{R}^V$ is measurable in a forcing extension $V[G]$ having new reals, then the measure must be $0$. The point is that every new real $x$ in $V[G]-V$ is transcendental over $\mathbb{R}^V$, and so the translates of $\mathbb{R}^V$ by the powers of $x$ are disjoint. Thus, a Vitali-style argument shows that if $\mathbb{R}^V$ is measurable, it must have measure zero. Gunter Fuchs and I made this observation in connection with [this related MO question](http://mathoverflow.net/questions/56990/probabilities-independent-of-zfc), but it may have been known previously.