One of the country's toughest congressional races is in Iowa between Republican Rep. Steve King and the state's former first lady, Christie Vilsack.

Iowa is losing a seat in the House after the election, due to redistricting. Now ultra-conservative King is facing a more moderate electorate as he runs in the newly redrawn 4th Congressional District against a political newcomer.

This week, King and Vilsack took their messages to the Iowa State Fair, a magnet for political candidates. President Obama and Republican vice presidential candidate Paul Ryan have also appeared there in recent days.

Up at the pork tent, King worked a long line of hungry fair-goers.

"Ready for my pork chop?" a fair-goer asked King.

"I had a little bite," said King. "I tested 'em out for you. I'm here to tell you, avoid the veggie burger — go for the chops," he joked.

The new district is believed to be more moderate, since it includes the college town of Ames, home of Iowa State, a massive agricultural research university. King says people should vote for him because he's a product of the area; Vilsack moved to Ames to challenge King.

"[My wife] Marilyn and I have been married for 40 years," King said. "Our three sons that are now grown have only known one father, one mother, one house, one church, one school."

King reached out to shake Ginny Huntington's hand, but she refused.

"You're American, aren't you?" King asked the fair-goer.

Huntington told him she's very American, and later told NPR: "I could never vote for anyone like that. ... Ever."

King has a track record of bluntly speaking his mind. In 2008, King said if then-Sen. Barack Obama won the presidential election, terrorists would be dancing in the streets. And he was the only member of Congress to vote against a plaque recognizing slaves who built the U.S. Capitol.

But he's been doing something right: He's won every election since he first came onto the political scene 10 years ago. But that was in the state's 5th Congressional District, which comprises the state's western-most counties, and which, as of January, won't exist. The newly drawn 4th District includes only sections of King's current district, extending further east — but not as far south — in the state.

Still, like many in the line at the fair in Des Moines (which is just south of the new 4th District), Lyle Fraizer of Denison said King has his vote.

"He's been there doing the job," said Fraizer. "And I don't like the lady. ... It's a man's world."

Vilsack, a former teacher, was the state's first lady in the administration of Gov. Tom Vilsack in the early 2000s. Tom Vilsack is now agriculture secretary for President Obama.

If elected, Christie Vilsack would be the first woman sent to Washington by Iowa voters.

Sylvia Vust of Ellsworth, Iowa, said she's tired of King representing her state. She's critical of "things he's said, and the thing he stands for."

"It's no decision for me at all," Vust said. "Christie embodies everything that I support."

After delivering a political speech at the fair, Vilsack mingles with supporters.

"They should vote for me because my lens is local," she said. "And because I want to be an advocate every day for the two years I'm there, for the things they care about, whether it's creating trade opportunities for farmers or revitalizing small towns."

But Dennis Goldford, a political scientist at Drake University in Des Moines, said Vilsack "needs to develop a toughness and aggressiveness that King already has."

Both candidates have raised more than $2 million each, and they're running about even in superPAC strength. But the Center for Responsive Politics says most of Vilsack's big contributions, those exceeding $200, came from out of state.

Money aside, Goldford says it might come down to voters in Story County, specifically in the college town of Ames, an area not currently in King's district.

"Christie Vilsack has to activate a Democratic base, not huge outside of Story County," said Goldford. "King will have Republicans solidly. In fact, rather than Romney providing coattails for King in Iowa, King will provide coattails for Romney."

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