Agriculture Secretary Tom Vilsack (Brendan Hoffman/Getty Images)

Vilsack said she plans to run against Rep. Steve King (R-Iowa) in the state’s new 4th Congressional District. Iowa’s redistricting plans are merging King’s current district with that of Rep. Tom Latham (R), who plans instead to challenge Rep. Leonard Boswell (D) in the state’s new 3rd Congressional District.

In a private meeting with Iowa Democrats Monday, local news reports quote Vilsack as saying that a race between his wife and King “will be a holy war.”

But during a USDA event in Minneapolis Wednesday, he declined to comment on the campaign because he was on official business. Aides said he’ll maintain that silence whenever he’s on duty.

“He understands the separation of politics and government and what we have to do. The same rules will continue to apply,” said an aide, who along with other USDA officials were not authorized to speak publicly on the matter.

In order to qualify for the race, the Vilsacks are moving their official residence to the town of Ames from Mount Pleasant, where the secretary was mayor. An aide said they also rent an apartment in Washington.

Despite her name recognition, Christie Vilsack faces a tough race: For one, Iowa is one of just a few states that has never elected a woman to Congress and has elected only one woman to statewide office. The 4th District’s Republican tilt also could prove daunting for a former Democratic first lady who backed John Kerry’s presidential bid during the 2004 Iowa caucuses and Hillary Rodham Clinton in 2008. (Clinton campaign aides complained back then that they failed to win the state’s caucuses because of its unfamiliarity with female candidates.)

If Christie Vilsack wins the race, she and her husband would join a choice group of Washington power couples who have served simultaneously in the Cabinet and Congress.

Elaine Chao, wife of Senate Majority Leader Mitch McConnell (R-Ky.), served as labor secretary for the duration of George W. Bush’s administration. Elizabeth Dole, wife of then-Sen. Robert Dole (R-Kan.), served as transportation secretary for Ronald Reagan and then as labor secretary for George H. W. Bush. Wendy Lee Gramm also served during some of the Reagan years as head of the Commodity Futures Trading Corporation while her husband, Phil Gramm (R-Texas), served in the House and Senate.

In a December interview with Radio Iowa, the secretary said he would support his wife’s final decision on running and would not leave his current job.

“Secretary Chao and Senator McConnell were married during the Bush Administration, so I don’t think there’s any legal prohibition against it,” he said.

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