(CNN) -- President Barack Obama laid out a sweeping defense of his domestic record Wednesday while blasting his Republican opponents as political opportunists and defenders of a bankrupt economic philosophy.
Noting that the economy has grown for three quarters in a row, the president claimed credit for "breaking the free fall" and building a new foundation for growth "without much help from our friends in the other party," he said. Republicans have mostly "sat on the sidelines and shouted from the bleachers," he said.
The president's remarks, delivered in the perennial swing state of Pennsylvania, were the latest partisan salvo in the run-up to November's heated midterm elections.
The Republicans will campaign on "the same promises they've been making for decades," Obama said in a speech at Pittsburgh's Carnegie Mellon University. But for much of the last 10 years, "we tried it their way ... [and] know where those ideas will lead us."
"We can go backward or we can keep moving forward," he said. "We need to keep moving forward."
Obama's trip to Pennsylvania was his fifth since taking office. The president arrived in Pittsburgh with Sen. Arlen Specter, D-Pennsylvania, who was recently defeated by Rep. Joe Sestak in a tough Senate Democratic primary fight. Obama had endorsed Specter.
Some of the GOP opposition to his agenda, Obama asserted, "is just politics. Before I was even inaugurated, the congressional leaders of the other party got together and made a calculation that if I failed, they'd win."
But much of the Republican position is also "rooted in their sincere and fundamental belief about government," he said. "It's a belief that government has little or no role to play in helping this nation meet our collective challenges. It's an agenda that basically offers two answers to every problem we face: more tax breaks for the wealthy and fewer rules for corporations."
The president predicted that "as November approaches, leaders in the other party will campaign furiously on the same economic argument they've been making for decades. Fortunately, we don't have to look back too many years to see how it turns out."
Obama blamed the GOP for providing tax cuts to "millionaires who didn't need them" while gutting regulations, putting "industry insiders in charge of industry oversight" and turning record budget surpluses into record deficits.
"We already know where their ideas led us," he said. "And now we have a choice as a nation. We can return to the failed economic policies of the past, or we can keep building a stronger future."
The president also used the oil spill crisis in the Gulf of Mexico to advance his alternative energy agenda Wednesday, calling it a warning that America needs to transition away from dependence on fossil fuels.
"The catastrophe unfolding in the Gulf right now may prove to be a result of human error -- or corporations taking dangerous shortcuts that compromised safety," he said.
"But we have to acknowledge that there are inherent risks to drilling four miles beneath the surface of the Earth -- risks that are bound to increase the harder oil extraction becomes. Just like we have to acknowledge that an America run solely on fossil fuels should not be the vision we have for our children and grandchildren."
Obama acknowledged that the Democratic leadership's energy reform plan doesn't currently have the votes to clear the Senate but promised to keep pushing for the bill's passage.
A Quinnipiac University poll conducted in early May indicated that 46 percent of Pennsylvania voters approve of the job Obama's doing as president, wtih 48 percent opposed. Obama beat GOP Sen. John McCain of Arizona by 11 percentage points in Pennsylvania in 2008.
CNN's Alan Silverleib and Paul Steinhauser contributed to this report.