Republican Donald Trump is surging in Iowa with a week to go before the first votes are cast in the 2016 U.S. presidential election process.
A Fox News poll shows Trump moving into a big lead over Texas Senator Ted Cruz by a margin of 34 to 23 percent, with Florida Senator Marco Rubio in third place with 12 percent.
A new CBS News Battleground Tracker online poll shows Trump with a smaller lead over Cruz at 39 to 34 percent, with Rubio trailing at 13 percent.
These latest surveys show Trump gaining support with less than a week to go before the February 1 Iowa caucuses, the first official voting test of the 2016 campaign.
'I want to win Iowa'
Trump told supporters in Muscatine, Iowa, that he is making an all-out effort in Iowa. “I want to win Iowa, I want to really win it,” he said.
Trump's poll surge comes after Cruz was put on the defensive when Trump raised questions about his eligibility to be president because Cruz was born in Canada to an American mother.
The latest polls also show Trump holding a big lead in New Hampshire, which follows Iowa with the first in the nation presidential primary on February 9.
The latest Fox News poll shows Trump with 31 percent in New Hampshire followed by Cruz with 14 percent and Rubio at 13. Ohio Governor John Kasich received 9 percent support in New Hampshire followed by former Florida Governor Jeb Bush and New Jersey Governor Chris Christie, both at 7 percent.
The polling news for Trump is also encouraging in South Carolina, which votes later in February.
The CBS News on-line poll has Trump ahead with 40 percent support from Republican primary voters, followed by Cruz at 21 percent and Rubio at 13 percent. The top Republican contenders meet for one more debate Thursday in Des Moines, their last before next Monday's caucuses.
Tight democratic race
Democrat Hillary Clinton and her main challenger, Vermont Senator Bernie Sanders, remain locked in a very tight race in Iowa, according to the latest polls.
The CBS News Battleground Tracker online poll shows Sanders with a 1-point lead over Clinton, 47 to 46 percent, with a week to go until the caucuses.
Former Maryland Governor Martin O'Malley is well back at 5 percent.
Sanders has also built a large lead in New Hampshire, according to the CBS poll, and now leads Clinton 57 to 38 percent, no doubt helped by the fact he is from neighboring Vermont.
Clinton, however, leads Sanders in South Carolina by a large margin, 60 to 38 percent.
Clinton supporters have long maintained their candidate will have an advantage in Southern states that vote later in the primary schedule and that could counterbalance success by Sanders in the early-voting states of Iowa and New Hampshire.
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Clinton has stepped up her attacks on Sanders in recent weeks, questioning his experience on foreign policy and accusing him of flip-flopping on the issue of gun control.
"I believe I have the experience, the judgment and the vision to get us back moving, further than we got with President [Barack] Obama,'' she told supporters in Iowa.
Sanders has been aggressive in responding not only to Clinton but to her husband, former President Bill Clinton, who has also questioned whether Sanders could win the general election.
He told The Washington Post, “Our campaign is not going to simply sit back and accept all of these attacks. We are going to win this thing.”
Obama weighs in
Obama, who remains neutral in the Democratic race, also weighed in on the primary battle between Clinton and Sanders in an interview with Politico.
He described Clinton as “wicked smart,” but also said Clinton's experience in government has lead to her campaigning “more in prose than poetry.” He said Clinton came into the race with both the “privilege and burden of being the perceived front-runner.”
Obama contrasted Clinton's situation with Sanders' more idealistic approach and said Sanders has been able to tap into what he called “a running thread” in Democratic Party politics that encourages people to be “full-throated in our progressivism.”
He also said he understands why that view has appeal to Democratic voters.
Obama said that Republicans Trump and Cruz were exploiting anger and frustration within the Republican Party and expressed the hope that voters will “settle down” when they consider “who do we want actually sitting behind the [Oval Office] desk.”
Eight years ago, Obama rocked the political world with his first-place finish in Iowa over challengers John Edwards and Clinton.
The Democratic primary battle in 2008 went on for months, but Obama was able to hold his lead after his initial victory in Iowa.
Obama told Politico that his time campaigning in Iowa and his eventual win there was “the most satisfying political period in my career.”
