Scarlett Johansson sings in a new music video supporting U.S. presidential candidate Barack Obama.

The 'Lost in Translation' actress joined her fellow stars, including Pussycat Dolls singer Nicole Scherzinger and Wyclef Jean in lending her voice to promotional video 'Yes, We Can' to drum up votes for the Democrat politician.

Former Vice President and Nobel laureate Al Gore was shown making a speech in support of gay marriage. A week-old video of him openly announcing his endorsement was posted on his website Current TV. The video was titled, "Gay men and women should have the same rights."

"I think that gay men and women ought to have the same rights as heterosexual men and women, to make contracts, to have hospital visiting rights and to join together in marriage," Gore announced. "And I don't understand why it is considered by some people to be a threat to heterosexual marriage to allow it by gays and lesbians."

David Letterman got close to former North Carolina Sen. John Edwards Tuesday night on "The Late Show." Edwards got away with a quick tease to his hair, but failed to walk away with an endorsement from the late night host.

Edwards made an eight minute appearance on "The Late Show" that gave the candidate a chance to dazzle viewers with his sense of humor and to discuss is campaign. Letterman teased Edwards about his notorious $400 haircuts, but a gracious Edwards gave the host permission to touch his immaculately manicured coif.

Sen. Hillary Clinton (D-NY) on Tuesday announced that singer and Oscar-winner Barbra Streisand has endorsed her campaign.

"Madame President of the United States... it's an extraordinary thought. We truly are in a momentous time, where a woman's potential has no limitations," Streisand said in a statement released the Clinton campaign. "Smart, capable and strong in her convictions, Hillary has transcended the dictates of what is thought to be possible for our time."