52-year-old Casey is running for a second, six-year term while 65-year-old Smith is a Tea Party favorite and political newcomer.
Smith paints Senator Casey as a big spending liberal and a rubber stamp for President Obama while Sen. Casey says Smith is a Tea Party darling who will appeal the president's affordable health care plan.
"This election is about jobs, we know that. The affordable care act is one of the reasons why business are so afraid to expand and hire," said Smith.
"The worst thing we could do on healthcare is put our head in the sand and do nothing, which is what repeal means. We need to make it work, protect our kids and make sure our seniors are protected on Medicare," said Sen. Casey.
What about reforms on Wall Street and possibly breaking up the big banks?
"I voted in favor of the legislation to finally crack down on the abuses in Wall Street. The kind of roulette people play with money that folks invest, powerful interest, making deals and scheme artist that are undermining our economy," said Sen. Casey.
"I'm beholding to no one. I was a democrat and I had to leave them because of some of their policies," said Smith.
The candidates also dueled over their anti-abortion positions, Medicare and cuts in federal spending.