It was an experience that turned him vehemently against President Bush and a war he now believes can never be won definitively.

“Iraq is a symptom of what’s wrong with this Administration,” Mr Horne told The Times over coffee near his Kentucky law office.

“It’s hubristic. It’s wedded to political cronyism. It hides the truth. It ignores advice. I want to go to Washington to be part of a solution.”

Mr Horne, 44, is not alone. He is one of a dozen Iraq war veterans running for congressional seats in the November mid-term elections. What makes this new band of political brothers extraordinary is that all but one are running as Democrats, and against a war that only months ago they were fighting in.

“It’s unprecedented. It’s amazing the Democrats have found this many,” said Larry Sabato, a politics professor at the University of Virginia.

Thirty military veterans from the wars in Vietnam, Bosnia, Afghanistan and Iraq are seeking seats in the US House of Representatives as antiwar Democrats in a country where more than half the public now consider the war a mistake.

The only Iraq veteran running as a prowar Republican is Van Taylor, a decorated Marine captain challenging a Democrat incumbent in Texas. Republicans also have 35 candidates for House seats who fought in other wars.

The Democrat veterans have been aggressively recruited by a party desperate to burnish its national security credentials, and keen to exploit the two issues that its strategists believe most threaten the Republican grip on Capitol Hill: Iraq and congressional corruption.

They hope there will be nothing more appealing to voters and harder to attack than a candidate who has actually fought in Iraq and sees politics as another way to serve the country, not a means to free meals and foreign junkets courtesy of lobbyists such as Jack Abramoff.

Although many of the Democrat veterans will struggle to win, Mr Horne is one of several for whom the party has high hopes.

He is challenging Anne Northup, a five-term Kentucky Republican who backs the war.

The White House betrayed its concern at Mr Horne’s candidacy when Mr Bush chose Louisville, the heart of Ms Northup’s Kentucky seat, for a speech on Iraq. Ms Northup shared the stage with him.

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