Bruce Springsteen will perform at a Saturday afternoon rally to benefit Sen. Barack Obama on Benjamin Franklin Parkway, the Obama campaign has just announced. The Boss will play between 20th and 22nd streets. Gates open at 2 p.m. with the rally to begin at 3:30. Preferred tickets go to Obama campaign volunteers who visit one of his local campaign offices starting at 10 a.m. tomorrow. General admission tickets are to be available by clicking here, though as of yet there is nothing posted to the page. The address was provided by the Obama campaign.