NEW YORK — A controversial new study contends nearly 655,000 Iraqis have died because of the war, suggesting a far higher death toll than other estimates. The timing of the survey’s release, just a few weeks before the U.S. congressional elections, led one expert to call it “politics.” In the new study, researchers attempt to calculate how many more Iraqis have died since March 2003 than one would expect without the war. Their conclusion, based on interviews of households and not a body count, is that about 600,000 died from violence, mostly gunfire. They also found a small increase in deaths from other causes like heart disease and cancer. “Deaths are occurring in Iraq now at a rate more than three times that from before the invasion of March 2003,” Dr. Gilbert Burnham, lead author of the study, said in a statement. The study by Burnham, of the Johns Hopkins Bloomberg School of Public Health, and others is to be published Thursday on the Web site of The Lancet, a medical journal. An accurate count of Iraqi deaths has been difficult to obtain, but one respected group puts its rough estimate at closer to 50,000. […]