Newt Gingrich's status as Republican front runner is fading after weeks of attack ads from rivals and intense media exposure of his political history and personality.
A Public Policy Polling survey of likely Republican caucus-goers in the key state of Iowa released on Monday showed the former House speaker dropping to third place there from first in the space of a week.
His lead also has evaporated in national poll.
"Newt Gingrich's campaign is rapidly imploding and Gingrich has now seen a big drop in his Iowa standing two weeks in a row," Public Policy Polling, which is affiliated with the Democratic Party, said in a statement.
Gingrich earned just 14 percent in the latest Iowa poll compared to 22 percent a week ago and 27 percent two weeks ago.
Congressman Ron Paul took over the lead with 23 percent, a five point increase over the past weeks. Former Massachusetts Governor Mitt Romney, Gingrich's main national rival, was second with 20 percent.
The survey of almost 600 people, taken Dec. 16-18, had a 4 percentage point margin of error.
Another poll, by CNN/ORC International, showed that Gingrich and Romney were tied on 28 percent of support nationally from Republicans and Republican-leaning independents.
An outpouring of television and radio commercials by Gingrich's opponents that paint him as unreliable and a Washington insider has taken a toll.
"It's tough not to feel the effects in millions of dollars in advertising spent against you with no comparable response," said Tim Albrecht, spokesman for Republican Iowa Governor Terry Branstad and a former Romney staffer during his first run for president in 2008.
Gingrich's personal favorability numbers also fell during the past fortnight from plus 31 to plus 12 to a minus 1 now among Iowa voters polled ahead of the Jan. 3 Iowa caucus, the polling firm said.
STILL TIME FOR MORE SEESAW MOVES
Gingrich's front-runner status has prompted attacks from rivals who say he is an unreliable conservative and influence peddler, particularly because of fat fees he earned from Freddie Mac, a mortgage giant tied to the economic recession.
"(Gingrich) is taking an unprecedented beating ... I have just never seen so many negative, substantively negative ads aimed at one candidate from so many different angles," said Cary Covington, a professor of political science at the University of Iowa. "Ron Paul is just eviscerating Newt Gingrich in the ads."
Iowa political operatives cautioned that there was still plenty of time for more changes in the two weeks left before the nominating caucus, which is the first of the 2012 presidential campaign.
"Newt may have peaked at the right time or peaked just a little bit too early," said Will Rogers, one of the members of Gingrich's campaign team who resigned en masse in June amid frustration over how it was being run.
But Rogers, who has returned to support Gingrich as a volunteer and is heavily involved with the Republican Party, said polls only represented a snapshot in time and said it seemed that many Iowa voters still were undecided.
"You don't know where Iowans truly sit until Jan. 3," Albrecht said. "There's an unprecedented level of uncertainty this late.
"Caucuses always surprise people at the end. One thing caucuses do is defy conventional wisdom. Someone always dramatically outperforms poll numbers and someone under performs."
Gingrich has run an unorthodox campaign, signing books at events and talking about topics ranging from the economy to brain research and lunar mining.
"His campaign has been one of speeches and ideas, not one as organized as the others. And it's been interesting to watch at public forums and speeches, that people have gravitated toward him and liked what he's had to say," said John Gilliland, of the Iowa Association of Business and Industry.
"But it's hard when you're trying to build infrastructure when you're behind the eight ball," he said.
Rogers said libertarian-leaning Paul was reaping the benefits of having a strong ground organization in Iowa - unlike Gingrich who has been scrambling to beef up his staff as he rose in the polls.