HARRISBURG - Former Sen. Rick Santorum of Pennsylvania, a potential Republican presidential candidate, warned Monday that conservatives should be wary of the libertarian strain of thought in the "tea party" movement.

Santorum was responding to a question about Kentucky's Republican Senate nominee Rand Paul, who last week said the federal government had no right to bar private businesses, such as restaurants, from discriminating on the basis of race, as it did in the 1964 Civil Rights Act.

"I don't think the libertarians have it right when it comes to what the constitution is all about . . . or when it comes to our history," Santorum said at the Pennsylvania Press Club. "When there are clear wrongs in society, injustice in society - sure, you handle it at the local level if you can - but when the local and state governments are in cahoots with the injustice, then the federal government has to step in and do something."

After denunciations from the left and right, Rand backed away from his position and affirmed support for the public-accommodations section of the law. Santorum, along with most Republican officials, supported Paul's opponent in last Tuesday's primary, Trey Grayson.

Santorum also dismissed Pennsylvania's Democratic Senate candidate Joe Sestak as "a loose cannon" and predicted a November victory for Republican Pat Toomey.

Santorum said he notices a "sense of anxiety" among Americans as he stumps for conservative causes. Repeat trips to Iowa, South Carolina and New Hampshire - all important early states in the GOP presidential nominating process - in the last several months has put him on the list of possible candidates for 2012.

Joking that he was amazed at how a little presidential buzz had drawn people to hear his ideas, Santorum said he would not make a decision about whether to run until several months after the midterm elections in November.

Santorum, 52, served two Senate terms before losing a race for reelection in 2006. He is a fellow at a conservative think tank, a commentator on Fox News and talk radio, and writes a bi-weekly column for The Inquirer.

After his speech, Santorum predicted that Toomey would defeat Sestak in the fall.

"He is what Pennsylvanians have never elected: an unabashed, enthusiastic, wild-eyed Howard Dean," Santorum said of Sestak.

"The guy's a loose cannon," he said, noting Sestak's claim that the White House offered him a job if he wouldn't run against Sen. Arlen Specter.

"Joe Sestak ran one good commercial, and that's what beat Arlen Specter," he said, referring to an ad that linked Specter to then-President George W. Bush and him, using footage from the 2004 GOP primary. Otherwise, Santorum said, Sestak "ran a terrible campaign."

People are frightened of huge increases in federal spending and mounting debt, Santorum said, adding that it was vital to repeal President Obama's health-care overhaul program, which he said would create a new and unaffordable $1 trillion entitlement. Even more worrisome, he said, the program threatens the national character.

He said a Democratic member of Congress told him that the health-care plan would become more popular as people got "hooked" on its benefits.

"I had to close my eyes for a moment and think that, in some respects, I was on a street corner across from a high school listening to a drug dealer," he said, adding that the health-care plan will "numb" the next generation.

"Yes, it will take away the agony of defeat from them but also the thrill of victory," Santorum said. "It will dumb down and flatten us. We will no longer be a people or a country of peaks and valleys but of numbing middle ground."

Contact staff writer Thomas Fitzgerald at 215-854-2718 or tfitzgerald@phillynews.com.