Try as they might, Mitt Romney's rivals cannot seem to make Obamneycare stick.

A new poll released Thursday said more Republicans believe the former Massachusetts governor's views on health care policy are different than President Barack Obama's, despite the similarities of their respective efforts to cover the uninsured.

The Kaiser Family Foundation said 49 percent of Republicans surveyed felt Romney's holds different health care policy views than Obama, while nearly a third say they are the same.

There are reasons why Republicans have tried to tar Romneycare, signed in 2006, as the blueprint to Obamacare: the laws are anchored in a mandate to buy insurance, both feature insurance marketplaces called exchanges and both prevent changes in premiums based on current health or gender.

But the poll suggests that Romney has been able to dodge the attacks from his fellow GOP presidential contenders by unapologetically defending his health care law while disparaging Obama's Affordable Care Act.

This administration screwed up royally on public relations, said Graham Wilson, chair of Boston University's political science department. It allowed the Republicans to portray the legislation very negatively.

Romneycare v. Obamacare

When confronted during debates, Romney touts how popular the law is with Massachusetts residents and that the individual mandate -- the centerpiece to the Affordable Care Act -- applied to a relatively small number of people who were uninsured.

Making a play for conservatives, Romney has shaped the debate as devising a law uniquely tailored to a state, versus Obama's one-size-fits-all approach.

He's tried to make this into a state's rights issue, said Fred Bayles, a journalism professor at Boston University, who runs a program that covers the Massachusetts state house. I think that's his main argument and his main way of distancing himself from the Affordable Care Act.

Meanwhile, Romney has portrayed Obamacare as portrayed as a budget-busting job killer from the heavy-handed federal government.

A lot of people who don't pay a lot of attention to the politics of health care think, 'Oh, Romney's is different. Romney's is a sensible collection of reforms, said Chris Galdieri, assistant professor of politics at St. Anselm College in New Hampshire. But it's very much the model for what the Affordable Care Act implemented.

Another boon for Romney may be his Republican rivals' early reluctance to use the Massachusetts health care law as an attack. Even the one-time candidate who coined Obamneycare, former Minnesota Gov. Tim Pawlenty, famously refused to use the term during a debate when he was handed the opportunity.

Newt Gingrich once tried to use it against Romney during a debate, but that failed. Romney turned the tables on Gingrich, pointing out that the former House speaker had previously supported an individual mandate as part of health care reform.

Galdieri said that the attacks on Romney had stepped up considerably since his win in the New Hampshire primary, which could affect what Republican voters think about the Massachusetts health care law.

Rick Santorum, a former senator from Pennsylvania, has been one of the presidential contenders to tie Romney to the Affordable Care Act and Gingrich to the unpopular individual mandate.

We've seen Romney come under much more sustained criticism from his remaining opponents, Galdieri said.