Washington (CNN) - What a difference a couple of weeks make.
In late September Texas Gov. Rick Perry was the front-runner in national polls of the race for the Republican presidential nomination. But a new CNN Poll of Polls of the GOP race indicates that former Massachusetts Gov. Mitt Romney is on top of the field of candidates with Perry in the third slot.
The CNN Poll of Polls, an average of the three latest national surveys that was compiled and released Wednesday, shows Romney with the support of 20% of likely Republican primary voters. Romney, who's making his second bid for the White House, was the front-runner in most national polls until Perry jumped into the race in mid-August. Businessman, former Godfather's Pizza CEO and radio talk show host Herman Cain is at 17%, followed by Perry at 15%.
"Recent polls show Cain gaining at least 12 points and Perry dropping by about that much," says CNN Polling Director Keating Holland. "But Romney's support has barely moved. It suggests that the Romney supporters have made up their minds, while Romney opponents are moving from candidate to candidate to see who they really like."
No other Republican candidate made it into double digits in any of the surveys that the Poll of Polls is based on. The Poll of Polls indicates former House Speaker Newt Gingrich has 9%, Rep. Ron Paul of Texas with 7%, Rep. Michele Bachmann of Minnesota at 5%, former Sen. Rick Santorum of Pennsylvania at 3%, and former Utah Gov. and U.S. Ambassador to China Jon Huntsman at 1%.
"On average, these three polls had nearly one in four Republicans saying they didn't know who they would vote for or choosing a candidate who is not in the running," says Holland. "So there are plenty of undecided voters who will make the contest interesting when they ultimately decide who they support."
The current CNN Poll of Polls is an average of three surveys released in the past 24 hours: A CBS News Poll conducted Sept. 28-Oct. 2; a ABC/Washington Post Poll conducted Sept. 29-Oct. 2, and a Quinnipiac University Poll conducted Sept. 27-Oct. 3. The Poll of Polls does not have a sampling error.
The three surveys were conducted after Perry came under attack from rival campaigns over his stance on illegal immigration, border security, and Social Security, his uneven performance in the last GOP presidential debate two weeks ago, and his poor showing at a much watched straw poll in Florida a week and a half ago.
While not as crucial as polls in the early primary and caucus voting states, national surveys are a closely-watched barometer of the popularity of the candidates and a gauge of the strength of their campaigns.