explain, sheila krumholz, the difference between a pac and a super pac. is an independent expenditure on the committee and is a new breed of animal formed following the citizens united decision. last year, in january 2010, the supreme court decided in the citizens united versus the federal election commission case federal election commission case that they can spend directly on independence expenditures. these are political ads and that was really an earthquake in campaign finance law. it then precipitated another decision, speech now, which allowed for corporations and allows for groups to set up independent expenditure on the committees which filed with the federal election commission and can take an amount of money in any denomination to spend directly on a candidate's defeat or election. they are super because they have superpowers. they can receive money in excess of the normal pac's. host: stephen colbert said that his own pac. guest: he wants to sent up -- set up a super pac. they will be used to influence the 2012 election. he then had to go to th

washington journal" townhall guy benson and judd legum speak about the presidential race, and sheila krumholz will speak on "washington journal," live at 7 a.m. eastern on c-span. and tomorrow morning, former president clinton will speak about the federal deficit and middle east peace process. you can see his comments sunday at 10:30 a.m. eastern on c-span. >> people often say to me, and a good question, how much of your time do you spend writing and how much time doing research? great question, no one ever says how much of your time do you spend thinking. and that's probably the most important part. >> sunday with the interview with david mccullough, and his book, greater journey. and you can download at c-span.org/podcast. >> next bucknell university commentment address with erick weihenmayer. >> with erik weihenmayer, that is a passionate humanitarian, to overcome obstacles. despite losing his vision to eye disease at age 13, he's skier and mountain climber and acrobatic sky diver, in 2001 he climb the mount everest and in 2002, he was one of 11 and only first blind man to climb the seven

sheila krumholz talks about the political action committees that could impact the 2012 election. "washington journal" is live at 7:00 eastern on c-span. >> people often say to me, how much of your time you spend writing and doing research? that is a great question. nobody ever says, how much of your time do you spend thinking? that is probably the most important part. >> in part two of the interview with david mccullough, his writing process and greatest, -- latest, "the greater journey." you can download this as a podcast online. all this weekend on c-span, commencement addresses. we will now have to the university of colorado at boulder to hear from steve ells. after that, remarks from curtis carlson, the head of silicon valley firm. then, the national urban league president gives his commencement address to graduates at howard university in washington d.c.. [applause] the chipotle founder talked to students at the university of colorado at boulder. we will hear it now from the chancellor of the university who introduces mr. ells. >> today he is the founder, chairman, and co-ch