A political storm is brewing over Sen. Barack Obama's recent statements. Last Sunday, Obama was explaining his difficulty with winning over working-class voters in Pennsylvania and the Midwest, saying they have become frustrated with economic conditions:

"And it's not surprising then that they get bitter, they cling to guns or religion or antipathy to people who aren't like them or anti-immigrant sentiment or anti-trade sentiment as a way to explain their frustrations," Obama said.

The comments were posted Friday on The Huffington Post, creating a wave of criticism from Sen. Hillary Clinton, Sen. John McCain, and other politicians as the April 22 Pennsylvania primary draws near.

"The people of faith I know don't ?cling to' religion because they're bitter. People embrace faith not because they are materially poor, but because they are spiritually rich," Clinton said at a rally in Indianapolis.

Now, Obama is spending time explaining his remarks.

"Obviously, if I worded things in a way that made people offended, I deeply regret that," Obama said in a phone interview on Saturday with the Winston-Salem Journal. "But the underlying truth of what I said remains, which is simply that people who have seen their way of life upended because of economic distress are frustrated and rightfully so."

He continued, "People feel like Washington's not listening to them, and as a consequence, they find that they can only rely on the traditions and the things that have been important to them for generation after generation. Faith. Family. Traditions like hunting. And they get frustrated."

For a candidate who has been outspoken about faith, religion has created hurdles for his campaign. Just a few months ago, he was squelching rumors about whether he was a Muslim and in March, he was defending his pastor Rev. Jeremiah Wright. It'll be interesting to see whether he addresses these recent remarks at Sunday's Compassion Forum at Messiah College.

The audio of his Sunday statement is available below: