Incumbent Republican Charles Grassley – for now at least – is sitting comfortably ahead of his three leading Democratic challengers in the U.S. Senate race in Iowa.

A new Rasmussen Reports telephone survey of likely voters in Iowa finds Grassley, who is expected to seek a sixth Senate term this fall, leading all three of his rivals by two-to-one margins or more.

Capturing roughly 60% of the vote in every case, he is well above of the 50% danger mark for incumbents.

Unlike some Democratic incumbents in seemingly safe seats, Grassley as a Republican seems immune so far to the voter backlash against the stumbling national health care plan and the stimulus and bailout initiatives that Congress approved last year. Barack Obama carried 54% of the vote to win Iowa in 2008.

Against former Iowa House member Bob Krause, Grassley leads 59%to 26%. In September, he had a 56% to 30% lead over Krause.

The GOP incumbent posts a 59% to 31% lead over former U.S. Attorney Roxanne Conlin, who ran unsuccessfully for governor in 1982.

Grassley bests former State Senator Tom Fiegen 61% to 25%.

In all three contests, those who prefer some other candidate is in single digits and those who are undecided are at 10% or less.

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As the ranking Republican on the Senate Finance Committee, Grassley was one of the so-called “Gang of Six” who unsuccessful sought to produce a bipartisan health care reform plan. But he quit the effort and voted against the plan that ultimately emerged from that committee.

With the health care plan seemingly derailed, only 34% of Iowa voters now think Congress will be able to agree on a smaller, bipartisan plan this year. Fifty-eight percent (58%) say it’s not very or not at all likely.

Male and female voters both favor Grassley by wide margins over his three opponents.

Conlin performs best among Democratic voters, but all three Democrats lose anywhere from 22% to 30% of their own party’s vote to Grassley. The Republican carries voters not affiliated with either party by more than 35 points against any of the Democrats.

Grassley is viewed very favorably by 32% and very unfavorably by just 14%.

Three percent (3%) have a very favorable opinion of Krause, while seven percent (7%) regard him very unfavorably.

For Conlin, very favorables are 12% and very unfavorables are 21%.

Four percent (4%) view Fiegen very favorably, and 14% have an unfavorable view of him.

At this point in a campaign, Rasmussen Reports considers the number of people with a strong opinion more significant than the total favorable/unfavorable numbers.

Just four percent (4%) of Iowa voters have no opinion of Grassley. Among his Democratic challengers, 21% don’t know enough about Conlin to venture even a soft favorable or unfavorable opinion range. Roughly 40% have no view of Krause and Fiegen.

Nine percent (9%) of Iowa voters rate the U.S. economy as good or excellent, while 46% say it’s poor. Twenty-eight percent (28%) think the economy is getting better, but 40% say it’s worsening and 26% feel it’s staying about the same.

Following the Christmas Day terrorist attempt on a U.S. airliner, 69% in Iowa say another terrorist attack in the United States is at least somewhat likely this year. That figures includes 26% who say it’s very likely. Thirty-three percent (33%) say the government’s response to that incident was good or excellent, but 31% label it poor.

Iowans are almost evenly divided over whether the United States is safer today than before the September 11, 2001 attacks: 39% say yes, 37% say no. Sixty-eight percent (68%) support the use of full-body scanners at airports.

Forty-four percent (44%) of Iowa voters now approve of President Obama’s job performance, including 28% who strongly approve. Fifty-four percent (54%) disapprove of how the president is doing his job, with 36% who strongly disapprove. This is better than Obama’s job approval ratings nationally in the Rasmussen Reports daily Presidential Tracking Poll.

Several longtime Democratic House and Senate members already have announced that they will not seek reelection this November, and the upset GOP win last week in Massachusetts’ special Senate election has made incumbent Democrats even more nervous.

Democratic Senate incumbents who currently trail their challengers include Harry Reid in Nevada, Michael Bennet in Colorado, Blanche Lincoln in Arkansas and Arlen Specter in Pennsylvania. Barbara Boxer from California, Evan Bayh of Indiana and Russ Feingold of Wisconsin find themselves in more competitive races than usual.

Republicans lead open-seat Senate races in Delaware, Florida, Kentucky, Missouri, New Hampshire, North Dakota and Ohio. Democrats lead in Connecticut, and the race is close in Illinois. A commentary by political analyst Larry Sabato, suggests that if the election were held today, “the (59-seat) Democratic majority in the Senate would be reduced to just 52 seats.”

In 2008, Rasmussen Reports projected nationally that Obama would defeat John McCain by a 52% to 46% margin. Obama won 53% to 46%. Four years earlier, Rasmussen Reports projected the national vote totals for both George W. Bush and John Kerry within half-a-percentage-point.

In Iowa during the 2008 campaign, Rasmussen Reports polling showed Obama leading McCain by eight, 52% to 44%. Obama won by nine, 54% to 45%. Other Iowa polling that year showed Senator Tom Harkin defeating Christopher Reed 57% to 41%. Harkin won 63% to 37%. In the 2006 race for Governor of Iowa, Rasmussen polling showed Chet Culver leading Jim Nussle 49% to 45%. Culver won 54% to 44%. In 2004, the final Rasmussen Reports poll in Iowa showed George W. Bush and John Kerry tied at 48%. The final numbers were Bush 50% Kerry 49%.

See all Rasmussen Reports 2008 state results for president, Senate and governor. See 2006 results for Senate and governor. See 2004 state results for president.

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