Rainier Ehrhardt, Associated Press
Republican presidential candidate Sen. Ted Cruz, R-Texas speaks at the Freedom Summit, Saturday, May 9, 2015, in Greenville, S.C.

GREENVILLE, S.C. — Republicans making their pitch to be the party's 2016 presidential nominee aimed to out-do each other Saturday in arguing that President Barack Obama is a failed leader.

But hitting Obama with the usual critiques — from his 2010 health care overhaul to allegations of missteps on foreign policy to the rise in the national debt during his time in office — also made it hard for the gaggle of White House aspirants to stand out during a forum in South Carolina hosted by the conservative group Citizens United.

Wisconsin Gov. Scott Walker tried by touting his ability to beat whoever is nominated by the Democratic Party, reminding activists that he won three statewide elections in four years in a state twice carried by Obama.

"The last time a Republican carried the state for president was 1984," he said. "That's a tough state."

He even took the crowd back to his decision to run for county executive in heavily Democratic Milwaukee County. "Never ever had there been a Republican in that spot before," he said.

In an interview before his turn on stage, Louisiana Gov. Bobby Jindal pointed to his work on policy, saying he's the only potential candidate in the field who has "spent the last 18 months coming up with detailed ideas on health care, on foreign policy, on energy."

"We're the only potential candidate who has an idea on how you get rid of Obamacare," he said.

Rick Santorum, who won the Iowa caucuses in 2012 before fizzling out against eventual nominee Mitt Romney, warned that Republicans eager to retake the White House after Obama's two terms in office must stay focused on reaching working-class voters.

"We have to be a pro-worker party," he said. "We have to be the party for a rising tide lifting all boats. There are millions and millions of Americans who have holes in those boats."

Former Texas Gov. Rick Perry let loose a series of broadsides at Obama and his policies, drawing cheers from the crowd for a withering critique that covered immigration, the Affordable Care Act, the Islamic State militant group and the federal budget.

His bottom line: "We've seen gross incompetence. We're here to declare that we're not going to take it anymore," Perry said.

Speaking later Saturday were several declared candidates, including Florida Sen. Marco Rubio, Texas Sen. Ted Cruz, retired neurosurgeon Ben Carson and former executive Carly Fiorina.

Citizens United President David Bossie, whose group hosted the gathering on Saturday, dismissed the idea the large number of GOP candidates muddled their messages. He called the wide field an advantage.

"These men and women all believe in American exceptionalism," he said. He added that along with criticizing Obama, Republicans should focus their ire on the favorite for the Democratic nomination, Hillary Rodham Clinton — a point on which many in the crowd agreed.

"Any one of them would be better than the disaster we've got now," said Gary Gunderson of Abbeville, South Carolina. His wife, Margaret, chimed in: "Or Hillary."

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