State issues can be tricky for presidential field
And some observers questioned whether Romney's response had less to do with the GOP primary, which Ohio will hold well after the early voting states, and more to do with the general election and the need to woo independent voters.
On the other hand, Romney may lose the party loyalists he needs to get the GOP nomination by waffling on the matter.
"The people who would be paying the most attention to this are probably the base of the Republican Party, and that's why it has the potential to be most damaging to him," said veteran Ohio political scientist Gene Beaupre of Xavier University.
At one time, presidential candidates visiting Iowa would stumble over that state's pet issue: support for subsidizing ethanol, the fuel additive the state leads in producing. But the issue has faded as a litmus test in the years since Bob Dole, a strong advocate, won the Iowa caucuses while opponent Phil Gramm of Texas finished a disappointing fifth.
That hasn't stopped Romney this year from noting his support for - and Perry's opposition to - the federal renewable fuel standard as Romney seeks Iowa agribusiness' support.
In South Carolina, candidates always are asked about flying the Confederate battle flag on Statehouse grounds. Supporters say it honors heritage and valiant native sons; opponents, led by the NAACP, say it is a divisive reminder of slavery.
Republicans usually say the flag is a state matter, but Arizona Sen. John McCain said after losing the 2000 primary that he should have spoken out on the issue and admitted that he feared opposing the flag would scuttle his chances in the state.
This year, candidates campaigning in South Carolina have been all but forced to weigh in on Boeing's efforts to build a plant in the state.
And in South Carolina and Nevada, opening Yucca Mountain as a nuclear waste depository is a sensitive issue.
South Carolina's congressional delegation wants the site in Nevada opened to relieve the Savannah River site, which has been storing nuclear weapons waste. That made recent debate pronouncements by Romney, Perry and Texas Rep. Ron Paul against using the Nevada site hard to swallow for some South Carolina Republicans.
"It's got to go somewhere, and we can't wait for them to figure out where it's going to go," Republican Gov. Nikki Haley said. Voters "are going to want to know what their answers are to that."
In New Hampshire, candidates have had to weigh in on a right-to-work drive aimed at unions.
Romney has already voiced support, saying in an August stop in Claremont, N.H., that "people should have the choice of deciding whether or not they want to join a union and have union dues."
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