The Des Moines Register (6/7, Norman) reports, "President Bush arrives in Des Moines today to promote the permanent repeal of the estate tax as a boon for farmers, but Democrats insist the repeal is nothing more than a sop for the super-rich. Bush will be accompanied to Iowa on Air Force One by Rep. Greg Ganske, who advocates a rollback of the tax. His Democratic opponent in this fall's Senate election, incumbent Sen. Tom Harkin, does not. Harkin is expected to show up for the president's remarks at the World Pork Expo at the Iowa State Fairgrounds, where Harkin has a booth. However, Harkin aides said Thursday night that White House officials told Harkin he could not appear with the President because he did not vote for the tax cut. White House officials confirmed that Harkin was not invited. 'Sen. Harkin didn't support tax relief for hard- working Iowa families,' said Scott Stanzel, a White House spokesman. Harkin aides questioned how Bush could refuse to invite Democrats to a nonpartisan event paid for with tax money. White House officials said they invited members of Congress who backed Bush on tax relief." Harkin "said Thursday he would support a higher exemption for estates to benefit farms or closely held businesses but not a total repeal."