IF THERE is one region of America where the reversal of fortune for Republicans appears the most striking, it is Indiana: a state that President Bush won by 21 points in 2004 but where voter discontent could provide the key to a Democratic takeover of the House of Representatives in November.

Of the 20 Republican seats judged the most at risk, three are in Indiana, a political reality that even the most wildly optimistic Democrat could barely have hoped for only a few months ago.

Nowhere in Indiana is the Republicans’ peril so graphically on display than in the state’s 2nd congressional district, where Chris Chocola, the incumbent who was not even on the Democrats’ target list in January, is fighting for his political life.

Mr Chocola, seeking his third term, has tied himself closely to Mr Bush, and the key to their success in the district — the President demolished John Kerry in this part of Indiana 56 per cent to 43 in 2004 — has been its rural south.

This district is focused on the largely Democratic city of South Bend in the north, home of the University of Notre Dame, which provides a spectacular example of American exceptionalism: college sports.

As you travel through the district’s south, past vast cornfields, potato lorries, the Church of the Heartland and the Harvest Church, there is no doubt that this is deeply Republican territory. Mr Chocola won by huge margins here in 2004.

But the mood among many diehard Republicans has soured. There are local factors not helping Mr Chocola — the new Republican governor, Mitch Daniels, a former White House budget chief, has infuriated Indiana voters by altering their time zones — but two issues above all else are dragging the candidate down: an unpopular president and his war in Iraq.

“It’s Iraq. It’s the war,” Ben Daulton said, during a lunch of meat loaf and pasta at a meeting of the Kiwanis Club in Rochester, a charity dominated by elderly Republicans. “I voted for Chocola and Bush. Now I don’t know. The Iraq policy is not succeeding. Without Iraq, Chocola would win hands down. If he loses, he can point to the war and the war alone.”

At the lunch, and elsewhere in Rochester, everybody had the same view: Mr Chocola faced possible defeat because of Iraq. And Mr Bush’s efforts to convince voters that Iraq was the central focus of the War on Terror appeared to be failing.

Roger Rose, a Republican county commissioner in Rochester, said: “Things are not going well in Iraq. Mistakes have been made. Chocola has drawn very heavily from President Bush in the past for support. He is now lagging in the opinion polls and the close association can do nothing but hurt Chocola.”

A recent poll put support for Mr Bush in Indiana at only 37 per cent. Mr Chocola concedes that this will have an effect. “The President’s approval ratings are lower than in the past. They influence every election around the country and I am not immune to that,” he told The Times.

Mr Chocola’s opponent is Joe Donnelly, a local businessman and moderate Democrat who lost in 2004 by nine points. Recent polls have him just ahead. “As I travel across the district, over and over again I hear a call for change,” he said — a soundbite echoing around America from nearly every Democratic candidate.

“Indiana is the key,” Amy Walter, a non-partisan analyst, said. “It is literally the centre of the Universe right now.”

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