Rilo Kiley was fairly full last time at the Black Cat but not sold out, and I believe that was a weekend night.  Their openers last time, The Good Life and Mayday, probably drew more than M Ward and the Statistics will, but they are still promising openers.  They do not have a new album out, although Jenny Lewis may have got some exposure from her work with Postal Service.  They also have not been getting radio play that I know of, other than on XMU.  I don't think it will sell out.