The Romney campaign has taken to claiming that the Obama administration raised taxes on “millions of Americans.” Post fact checker Glenn Kessler asked the Romney camp to justify the claim, and Romney advisers provided Kessler with a list of tax increases under Obama.

Most of them are in the Affordable Care Act, and haven’t been implemented yet. The main tax increase the Romney camp cited, which is in fact in effect right now, was this one:

The one, non-health-care-related, broad-based tax on Romney’s list is a 61-cent-per-pack increase in the federal excise tax on cigarettes. Obama signed this into law shortly after taking office in order to fund an expansion of the children’s health insurance program. About 45 million people in the United States smoke cigarettes, according to the Centers for Disease Control, and the percentage of smokers is higher among those living below the poverty level.

Assuming one smokes a pack a day, that would amount to $223 in increased cigarette taxes a year.

Romney, then, opposes this Federal excise tax on cigarettes to fund the expansion of the Children’s Health Insurance Program, or CHIP.

Romney spokesman Eric Fehrnstrom, in an interview with Kessler, pointed out that the tax would hit 45 million smokers, adding: “how many are unemployed? They have only gotten a tax increase (and a mighty regressive one at that).”

This raises a really interesting question for the Romney campaign, and I hope reporters ask it: If Romney opposes this tax, does that mean he also favors rolling back the CHIP expansion?

The answer to this question could feed into the current political debate. The CHIP expansion, which Obama signed into law in February 2009 and which stands as one of his key accomplishments, is designed to provide federally funded health care to four million more children — the children of parents who make too much to qualify for Medicaid, but don’t make enough to afford private insurance.

The expansion is paid for by the aforementioned cigarette tax, which Romney now opposes. So does he oppose the expansion? Would he favor rolling it back?

There isn’t an immediately easy answer to the question. If he says he does oppose it, that gives Dems another talking point — Romney could do away with health insurance for millions of kids. This presumably wouldn’t help Romney in the ongoing battle for women voters, many of whom probably support funding health insurance for kids with a tax on smokers.

If Romney says he supports keeping the program, it’s unclear how that squares with his criticism of the cigarette tax. And it could anger people on the right: Conservatives opposed the CHIP expansion , which was voted against by most Congressional Republicans, because they saw it as a step towards socialized medicine. They could see a Romney declaration of support for it as more pivoting away from them.

If Romney says he supports keeping the expansion but not the current means of paying for it, then people will ask him how he would pay for it, and if he would fund it with federal money. This would also be a hard question politically to answer, and would go to the heart of the proper role Romney envisions for government and the safety net.

These are good questions for the Romney camp. Someone should ask them.