(USA Today) — Former Massachusetts governor Mitt Romney questioned Wednesday whether Texas Gov. Rick Perry could be elected to the White House, given his stances on Social Security and other issues, and he expressed skepticism that his rival had the experience to govern effectively if he did win.

Romney’s caustic critique in a phone interview with USA TODAY previewed likely confrontations tonight between the two leading contenders for the Republican presidential nomination at a Republican debate in Orlando.

Does that blunt talk make Perry unelectable?

Romney called it “a very disconcerting approach,” then argued that the views Perry outlined in a book he published last year, suggesting that Social Security was unconstitutional, are ones he won’t be able to easily disavow.

“Given the fact that the book is so recently published and he reiterated his position with television interviews, I think his position is now cast in concrete,” said Romney — who has been criticized for changing positions over the years on such issues as abortion rights.

The Perry camp shot back after Romney released questions he said the Texas governor should answer on Social Security, including details of how a pension system run by states rather than the federal government might work.

“Mr. Romney is again sounding like a Democrat, distorting the truth and trying to scare senior citizens,” Perry communications director Ray Sullivan responded in a statement. “Rick Perry and other conservatives are courageous enough to be honest about federal spending and entitlements, whether Mr. Romney and the liberals like it or not.”

Romney, who has given a very limited number of interviews this year, declined to speculate about why he hasn’t demonstrated more appeal with the GOP’s conservative base. He did say he hoped Alaska governor Sarah Palin would run for president, a decision she has said she would make by the end of this month