In a move that could help Democratic Presidential hopeful Barack Obama gain inroads with white, working class voters and business people, he gained an important endorsement from Pennsylvania Senator Bob Casey, who has strong ties with the labor class in that state.

So far, Obama has been trailing Hillary Clinton in Pennsylvania, which is heavy in white, middle class citizens and Catholics, both of whom have shown her preference in recent polls. She has gained the support of Pennsylvania Governor Ed Rendell, which has helped bolster her success in the state.

Casey's endorsement coincides with a six day push in Pennsylvania by Obama as he tries to gather support for the upcoming April 22 primaries, where 158 delegates are at stake. This is the biggest prize left in any upcoming primary, and a key decision in the nomination process.

Casey Believes Obama can Heal America

Senator Casey, who shares Obama's support of gun rights and opposition to abortion, has been described as a quiet and gracious man whose support is greatly appreciated, but was not fought hard to attain. Obama said he did not press hard for the Casey endorsement, but is very grateful to have it.

Casey said in a speech that he believed Obama has the necessary skills to lead America in a dangerous world, to take the nation in a new direction that will lead us back to prosperity, and to heal America's wounds.

When asked about the Casey endorsement, the Clinton campaign expressed their gratitude for the abundance of support they have received so far from the state of Pennsylvania. Representative John Murtha and Philadelphia Mayor Michael Nutter are among Clinton's supporters in the state.

Leahy Calls for Clinton's Withdraw from Campaign

Meanwhile, Chairman of the Senate Judiciary Committee, Senator Patrick Leahy of Vermont, urged Clinton to abandon her bid for the White House. In a radio interview that was broadcast earlier in the week, Leahy said he felt there was no chance of Clinton winning enough delegates to secure the Democratic nomination. He further stated that Casey's endorsement only underscored the support Obama has garnered so far. Leahy upheld Clinton's right to remain in the race, but said he felt she did not have a good reason to continue, and that the Democratic Party needed to come together in order to have a chance at defeating McCain come the November elections.

Pennsylvania is seen as a crucial state for the candidates, with elderly voters and white working class and business people opting for Clinton, while the younger voters seem to prefer Obama.

In an effort to boost support, Obama has stepped up his television campaign, and will be touring the state of Pennsylvania with Casey, who currently shows a 62 percent approval rating among Pennsylvania Democrats.

Securing the Pennsylvania nomination could prove to be a crucial turning point in the nomination process, with the decision still up for grabs as the Democratic National Convention in Denver approaches. Democrats are hoping to have a clear-cut candidate in the near future so they can begin strategizing on the November elections.