Barack Hussein Obama II (ⁱ/bəˈrɑːk huːˈseɪn oʊˈbɑːmə/; born August 4, 1961) is the 44th and current President of the United States. He is the first African American to hold the office. In January 2005, Obama was sworn in as a U.S. Senator in the state of Illinois. He would hold this office until November 2008, when he resigned following his victory in the 2008 presidential election.

Born in Honolulu, Hawaii, Obama is a graduate of Columbia University and Harvard Law School, where he was the president of the Harvard Law Review. He was a community organizer in Chicago before earning his law degree. He worked as a civil rights attorney in Chicago and taught constitutional law at the University of Chicago Law School from 1992 to 2004. He served three terms representing the 13th District in the Illinois Senate from 1997 to 2004.

Following an unsuccessful bid against the Democratic incumbent for a seat in the United States House of Representatives in 2000, Obama ran for the United States Senate in 2004. Several events brought him to national attention during the campaign, including his victory in the March 2004 Illinois Democratic primary for the Senate election and his keynote address at the Democratic National Convention in July 2004. He won election to the U.S. Senate in Illinois in November 2004. His presidential campaign began in February 2007, and after a close campaign in the 2008 Democratic Party presidential primaries against Hillary Rodham Clinton, he won his party's nomination. In the 2008 presidential election, he defeated Republican nominee John McCain, and was inaugurated as president on January 20, 2009. Nine months later, Obama was named the 2009 Nobel Peace Prize laureate. In April 2011, he announced that he would be running for re-election in 2012.

Mark Daniel Ronson (born 4 September 1975) is an English DJ, musician, music producer, artist and co-founder of Allido Records. He currently works with his band under the music alias of Mark Ronson & The Business Intl.

While his debut album Here Comes the Fuzz failed to make an impact on the charts, his second album, Version included three top ten hits and won Ronson a Brit Award for Best British Male Artist in 2008. His third studio album, Record Collection, was released on 27 September 2010.

Ronson was born at the Wellington Hospital, St John's Wood, to writer/socialite Ann Dexter-Jones and one-time band manager and real estate entrepreneur Laurence Ronson. His parents are of Ashkenazi Jewish descent, with ancestors from Austria, Russia, and Lithuania, and Ronson was brought up in Conservative Judaism. Ronson's family name was originally Aaronson, but his grandfather Henry Ronson changed it to Ronson. Ronson is the nephew of property tycoon Gerald Ronson. Ronson is related to British Conservative politicians Sir Malcolm Rifkind and Leon Brittan, as well as Odeon Cinemas founder Oscar Deutsch. Ronson has twin sisters who are two years younger than him, Charlotte Ronson, a fashion designer, and Samantha Ronson, a singer and DJ. Ronson also has five younger half-siblings. Alexander and Annabelle, through his mother's remarriage to Mick Jones as well as Henrietta, David and Joshua, through his father's remarriage to model Michele First. After his parents broke up, his mother married Foreigner guitarist Mick Jones, which contributed to a childhood surrounded by music.

Peter Gene Hernandez (born October 8, 1985), better known by his stage name Bruno Mars, is an American singer-songwriter and record producer. Raised in Honolulu, Hawaii by a family of musicians, Mars began making music at a young age. He performed in various musical venues in his hometown throughout his childhood. He graduated from high school and then moved to Los Angeles, California to pursue a musical career. Mars produced songs for other artists, joining production team The Smeezingtons.

Mars had an unsuccessful stint with Motown Records, but then signed with Atlantic Records in 2009. He became recognized as a solo artist after lending his vocals and co-writing the hooks for the songs "Nothin' on You" by B.o.B, and "Billionaire" by Travie McCoy. He also co-wrote the hits "Right Round" by Flo Rida featuring Ke$ha, and "Wavin' Flag" by K'naan. In October 2010, he released his debut album, Doo-Wops & Hooligans. Anchored by the worldwide number-one singles "Just the Way You Are" and "Grenade", the album peaked at number three on the Billboard 200. Mars was nominated for seven Grammys at the 53rd Grammy Awards, winning Best Male Pop Vocal Performance for "Just the Way You Are".