Rudy Giuliani was treated for prostate cancer. John McCain has been treated for melanoma, the most serious type of skin malignancy. Fred Thompson was diagnosed with lymphoma, a cancer of the immune system.

And as the LA Times’ Ricardo Alonso-Zaldivar explained in a good piece today, all three could be denied healthcare insurance under their own healthcare plans.

All three have offered proposals with the stated aim of helping the 47 million people in the U.S. who have no health insurance, including those with preexisting medical conditions. But under the plans all three have put forward, cancer survivors such as themselves could not be sure of getting coverage — especially if they were not already covered by a government or job-related plan and had to seek insurance as individuals.

“Unless it’s in a state that has very strong consumer protections, they would likely be denied coverage,” said economist Paul Fronstin of the Employee Benefit Research Institute, who has reviewed the candidates’ proposals. “People with preexisting conditions would not be able to get coverage or would not be able to afford it.”

It offers a helpful contrast between the downsides of the two parties’ approaches to healthcare. The problem with the Dems’ plans is that they’re expensive. The problem with the Republicans’ policies is that sick people of modest means can’t get health insurance.

The Republican presidential hopefuls seem to realize that their plans leave millions of vulnerable Americans behind, but also realize that the alternative is government regulation — specifically, telling insurers that they can’t exclude people with pre-existing conditions, and can’t price these people out of coverage. Given a choice between a large gap of uninsured and government-imposed safeguards for Americans, the GOP candidates prefer the prior.