WASHINGTON (CNN) - New Mason-Dixon polls released Sunday show the primary picture growing more, not less, uncertain with the first presidential voting less than a month away.
No Democrat in Iowa, New Hampshire or South Carolina has a lead safely outside the margin of error.
On the Republican side, former Arkansas Gov. Mike Huckabee appears to have a double-digit edge in Iowa, and former Massachusetts Gov. Mitt Romney an 8-point margin in New Hampshire – but South Carolina remains up for grabs, with five candidates registering in double digits.
In the Hawkeye State – where a Newsweek poll released Friday appeared to show Huckabee with a stunning 22 point lead – the Republican contest seems to be a three-person race, with Huckabee at 32 percent, Romney at 20 percent, former Tennesse Sen. Fred Thompson at 11 percent and no other candidate registering higher than single digits.
"All Iowa polls done in late November and early December showed Huckabee and Romney in a virtual tie," said CNN Polling Director Keating Holland. "Now we we now have two polls showing Huckabee with a statistically-significant lead. The race in Iowa appears to have radically shifted in the space of a week or less."
In the Democratic race, New York Sen. Hillary Clinton appears to lead Illinois Sen. Barack Obama by a statistically insignificant 2-point margin, 25 to 27 percent, John Edwards at 21 percent, and no other candidate registering higher than single digit support.
Clinton’s campaign pollster, Mark Penn, quickly downplayed the results. “These races are always roller coasters,” he said in a post on the Clinton campaign Web site, warning “poll reader beware.”
Caucuses are extremely difficult to poll accurately, due in part to the unpredictability of Election Day attendance.
Still, New York senator’s lead in Iowa has slid dramatically or disappeared in most recent surveys. The Newsweek poll showed Obama leading by 6 points, underscoring the chaotic nature of that race.
The race has also grown much tighter in New Hampshire, where Obama seems to be picking up steam, pulling to within 3 points of Democratic frontrunner Hillary Clinton, 30 to 27 percent. Edwards garners the support of 10 percent of likely Democratic voters polled.
The Republican contest is growing more competitive as well, with four candidates now registering double-digit support: Romney’s support has slipped to 25 percent, with former New York City Mayor Rudy Giuliani registering 17 percent, Arizona Sen. John McCain 16 percent and Huckabee 11 percent. Nearly one in six voters are undecided.
In South Carolina, Mike Huckabee has pulled into a narrow lead with 20 percent of the vote, followed by Giuliani at 17 percent, Romney at 15 percent, Thompson at 14 percent, McCain at 10 percent – and around a fifth of likely voters still undecided.
Clinton's lead over Obama in the Palmetto State – taken before this weekend’s Oprah-Obama primary state tour - is just 3 points in the survey, 28 to 25. John Edwards – who won the state during the last presidential primary voting – follows with 18 percent, and the rest of the field barely registering.
The MSNBC/McClatchy/Mason-Dixon polls, conducted December 3-6, surveyed 400 likely primary or caucus-goers in each state, with a margin of error of plus or minus 5 percent.
Meanwhile, Clinton leads Obama with 34 to 26 percent in Nevada – with the rest of the pack in the single digits – in another Mason-Dixon poll released Sunday in the Las Vegas Review-Journal. Voters there head to the polls January 19.
Giuliani leads the GOP pack in the Silver State with 25 percent, with Romney at 20 percent and Huckabee at 17 percent.
The Nevada survey was conducted December 3-5 and surveyed 625 registered voters. It had a margin of error of plus or minus 4 percentage points.
–CNN Associate Political Editor Rebecca Sinderbrand