Hip-Hop moguls Jay-Z and Russell Simmons got deep into the 2008 political process by endorsing Senator Barack Obama in his bid for President.

The Brooklyn MC made a call for change via an automated phone message encouraging voters to support Obama in tomorrow's primaries. "Bring your friends and families make sure your voices are heard for change," "Jay-Z said. "It's time for change. It's time for Barack Obama." [Listen here]

Meanwhile, according to the Associated Press, Simmons said Sunday (March 2) he was inspired by the diversity among supporters of the Illinois senator.

"Obama has built an unprecedented national movement of people from all ethnic, racial, political, social and economic backgrounds," read a news release from the Def Jam founder.

Previously Simmons, who says he's an independent, had been undecided about who to vote for in the upcoming presidential race.

"If you could take Barack Obama's image, add Hillary Rodham Clinton's money and John Edwards' voice, that would be my candidate," Simmons was quoted back in January 2007.

While Simmons' official endorsement went to Obama, he also remarked on his great respect for Clinton, who he has previously worked with on education, prison reform and anti-poverty programs.

In related news, known Obama supporter Mos Def recently voiced his opinion on why the Illinois senator has been so popular.

"America's too vain, and he appeals to America's sense of vanity," Mos Def told Rolling Stone. "It's the A & R guy in me . . . when I saw him on the cover of Men's Vogue, I said, 'This guy's gonna win because he looks good.' So, the best-looking guy for the job is a black guy. I'm cool with that. People also want a rock-star quality to the president, which he has."

The race for delegates will reach a fever pitch tomorrow when both Democratic and Republican voters cast their ballots in Ohio, Rhode Island, Texas and Vermont. Many experts believe that Hillary Clinton will be unable to secure the Democratic nomination without winning the Ohio and Texas primaries.

Celebrity endorsements continue to pour in for Obama with the latest will.i.am video "We Are One," which features Jessica Alba, Ryan Phillippe, John Leguizamo, Macy Gray, Tyrese, Kerry Washington, Tichina Arnold, George Lopez, and Regina King. The video is based on a speech Obama delivered following his February 5th Super Tuesday primary victories: "We are the ones we've been waiting for, we are the change that we seek." [Watch video below]