[Plugin: Multi Rating Pro] Adjusting Sidebar Widget Width

I am using the MH Magazine theme, and I have the Multi Rating Pro Form widget on the sidebar. This is used by users to submit a review for the desired post. However, the comment box is cut off on the right hand side, causing the words typed into the comment box to not show up on that side. Is there a way for me to adjust the width of the forum widget on the side bar (officially the widget is mrp_rating_form).

Thank you!