main page post width in FREE Swift WP themes

i have a wide ‘gap’ between where the post shows and the sidebar, on my main index page. it’s basically where one can add ads like adsense, etc. i do not use this section but it shows up as a wide blank space.

does anyone know where i can make adjustments for this? to lessen or remove this section of empty space?

this only happens on main page. if you click on any post to read rest of post contents the post width is normal.

thanx in advance,
alx

http://wordpress.org/extend/themes/swift/