Hi there,
Actually the only solution in your case is to look at the html and css of the page (you can for example do a right click on the button and use the "inspect element" function of your browser) in order to see which css property could solve the problem.
In you case, I think it wont be easy because the button is simply aligned on the vote and product name. So if you look, the space between the stars and the button is always the same.
A solution is to set an absolution position for your buttons but it's not very convenient.
I hope it helped.