The joust between Hillary Clinton and Barack Obama over their dueling "universal" health care proposals is boiling over.

Clinton campaign manager Patti Solis Doyle has written a letter to her counterpart at the Obama campaign, asking the Illinois senator to stop running what she calls a "false ad" in New Hampshire that claims his health care plan would cover everyone.

"Your advertisement not only contradicts the judgment of health care experts but public statements by your campaign and your candidate," Solis Doyle wrote, adding, "Senator Obama has pledged to put 'honesty first' in this campaign. In that spirit I respectfully request that you stop running this ad which is misleading voters in New Hampshire."

The letter is the latest dig in an argument that has been percolating for weeks. Clinton's plan includes an individual mandate that would require every American to obtain health insurance, while Obama's plan only mandates coverage for children.

Clinton’s camp often cites experts who say Obama’s plan would leave out 15 million people of the 47 million who are uninsured and notes that even Obama has called the plan "virtually universal." Obama has said he would offer subsidies to the working poor, and that over time the savings through his plan would allow everyone to be covered.

But Obama chalked up the ongoing spat to "scoring points" while addressing the Democratic National Committee Friday in Vienna, Va.

"Here's the truth — if you can't afford health insurance right now, you will when I'm president," he said. "Anyone who tells you otherwise is more interested in scoring points than solving problems. And I'm in it because we've had enough of that."

The Obama campaign says Hillary is playing politics, pointing out that the ad in question is old news.

"The Clinton campaign didn't say a word when this ad was released a month ago, and the only thing that's changed since then is the poll numbers," Obama spokesman Bill Burton said.

A recent poll from the American Research Group showed Obama with 27 percent support in Iowa, over Clinton with 25 percent and John Edwards with 23 percent. The poll was taken from Nov. 26 to Nov. 29 of 600 likely Democratic caucus-goers. The margin of error was 4 percent.

The health care ad in question first aired in Iowa and resurfaced Thursday in New Hampshire. In it, Obama talks about his mother's death from cancer and about how much she worried about her medical bills. He says his plan would "cut costs and cover everyone."

Asked if the campaign would pull the ad over Clinton's letter, Burton said, "No way."

Burton said Obama's plan would offer coverage to everyone who can't afford it and that "rather than spending their time attacking Barack Obama, the Clinton campaign should explain how exactly they plan to order every American to buy health insurance even if they can't afford it."

Clinton's campaign claims her plan will make it affordable by aggressively cutting costs and capping the percentage of income every American would pay in health care premiums — something no other Democrat would do.

FOX News' Aaron Bruns and Bonney Kapp contributed to this report.