In the new survey, 54% of Republicans said they hold a favorable opinion of Romney, while 67% said the same in January. Among all Americans, 34% described the candidate as likable, down from 41% last month.
Meanwhile, Santorum's recent victories have boosted his standing among Republicans, 56% of whom had a good opinion of the former Pennsylvania senator, up from 49% in January.
The survey was conducted Friday through Monday, the tail end of a big week for Santorum with three contest victories followed by a spike in fundraising and poll numbers.
But among all Americans, Santorum's favorable rating has remained flat. Thirty-two percent held a good opinion in the new survey, while 31% said the same in January.
Texas Rep. Ron Paul and former House Speaker Newt Gingrich received positive reviews from roughly half of all Republicans.
But those numbers declined when Americans of all political affiliations were surveyed. In that case, Paul came in at 42%, ahead of Romney and Santorum, and Gingrich's favorable rating fell to 25%.
That leaves only one presidential candidate in the race with a national favorable rating above the 50% mark: President Barack Obama.
Among all Americans, Obama received positive reviews from 53%, with the poll suggesting he may have grown more popular in recent months.
CNN Poll: Romney’s likability fading – CNN Political Ticker - CNN.com Blogs
Meanwhile, Santorum's recent victories have boosted his standing among Republicans, 56% of whom had a good opinion of the former Pennsylvania senator, up from 49% in January.
The survey was conducted Friday through Monday, the tail end of a big week for Santorum with three contest victories followed by a spike in fundraising and poll numbers.
But among all Americans, Santorum's favorable rating has remained flat. Thirty-two percent held a good opinion in the new survey, while 31% said the same in January.
Texas Rep. Ron Paul and former House Speaker Newt Gingrich received positive reviews from roughly half of all Republicans.
But those numbers declined when Americans of all political affiliations were surveyed. In that case, Paul came in at 42%, ahead of Romney and Santorum, and Gingrich's favorable rating fell to 25%.
That leaves only one presidential candidate in the race with a national favorable rating above the 50% mark: President Barack Obama.
Among all Americans, Obama received positive reviews from 53%, with the poll suggesting he may have grown more popular in recent months.
CNN Poll: Romney’s likability fading – CNN Political Ticker - CNN.com Blogs