WASHINGTON (CNN) -- Surging in polls in Iowa, Republican presidential candidate Mike Huckabee finds himself increasingly under attack from rivals over his record as governor of Arkansas, particularly on taxes and immigration.
Former Arkansas Gov. Mike Huckabee's rise in polls has made him a high-profile target for his GOP rivals.
A Des Moines (Iowa) Register poll released Sunday shows Huckabee leading the Republican presidential field in Iowa with the support of 29 percent of likely caucusgoers, ahead of former Massachusetts Gov. Mitt Romney (24 percent) and former New York Mayor Rudy Giuliani (13 percent).
The newspaper poll's margin of error as 4.4 percentage points. It was conducted last week.
The survey was the first one in months that did not show Romney as the Republican front-runner in the Hawkeye state, which holds caucuses for both parties on January 3. Huckabee has been climbing in polls due to increased support from evangelical Christians, a key Republican voting bloc in Iowa.
In a sign that he may feel threatened, Romney has attacked Huckabee on immigration and taxes while he was Arkansas' governor.
"Gov. Huckabee fought in favor of giving in-state tuition breaks to illegal aliens," Romney told an audience Friday in Iowa.
The campaign of another GOP candidate, former Sen. Fred Thompson of Tennessee, has launched an ad criticizing Huckabee for raising taxes in Arkansas in 2003.
The conservative Club for Growth also ran an ad lambasting Huckabee for increasing taxes.
Huckabee has been trying to pre-empt these attacks, predicting that his opponents will say he was "a tax and spender" in Arkansas.
He boasted on Saturday that as governor he implemented "the first-ever, broad-based tax cuts and signed 94 different tax cuts."
While correct, Huckabee also raised taxes 21 times while governor, including a 16 percent increase in gas taxes and a 103 percent hike in cigarette taxes.
During his tenure in office from 1996 to 2007, Huckabee raised taxes overall by $505 million, according to FactCheck.org, citing an Arkansas Department of Finance and Administration official, who said the figure was adjusted for inflation.
Huckabee told CNN he has no regrets about the tax increases, saying they went to pay for schools and roads in Arkansas.
"There are times when that is necessary," Huckabee said. "Ronald Reagan raised taxes when he was governor of California. He raised taxes when he was president."
Huckabee also says he has no regrets about backing college tuition breaks for children of illegal immigrants or for fighting legislation that would have required proof of citizenship for state services.
"If you want national security handled by people at an entry-level state government, that's what you get, but I don't think anybody thinks that's a good idea," Huckabee said.
Rival campaigns privately are telling CNN they are considering attacking Huckabee for his role in the parole of convicted rapist Wayne DuMond.
DuMond was sentenced to life in prison, which Huckabee and others considered too harsh. After his parole in 2002, DuMond raped and killed another woman.
"It's horrible. I mean there's nothing any of us could ever do," Huckabee said. "None of us could've predicted what he could've done when he got out."
Huckabee said that the process leading to DuMond's release began under former President Clinton when he was governor of Arkansas.
But Huckabee admitted that he expects the DuMond case to become a campaign issue. E-mail to a friend
CNN's Dana Bash contributed to this report.