The NRA, a powerful lobby opposing gun control laws, has been a big supporter of Bush and the Republican Party over the years. It has given almost $390,000 to Republicans in the 2004 election cycle so far, according to the Center for Responsive Politics which tracks campaign contributions.

In comparison, Democrats received a little more than $58,000 this year from the organization.

During the tour, Bush will likely chat up his guests about several of his initiatives on clean air, wetlands and healthy forests, showing off the energy conservation features of his home and the native grasses that have been replanted, said White House spokeswoman Claire Buchan.

"The president has an aggressive conservation agenda and this is an opportunity to take a group of interested individuals on a tour of his ranch," she said.

While Bush proposed increasing the 2005 budget for forest fire programs and protecting endangered species, he has been criticized for trying to open up the Arctic National Wildlife Refuge to oil drilling and cutting the Environmental Protection Agency's budget by 7 percent for next year.

Bush is spending a week at the ranch, taking advantage of the upcoming Easter holiday and enjoying mostly sunny, warm weather. But his time away from Washington is not a full escape from his presidential duties.

In addition to his usual daily security briefings, he has held two special video conference calls to discuss the situation in Iraq, where insurgents have been inflicting heavy casualties on U.S.-led troops. Some 35 Americans and at least 200 Iraqis have died in the last three days.

Also last week morning, back in Washington his national security adviser, Condoleezza Rice, will is expected to defend the administration's actions on terrorism under oath before the commission looking into the Sept. 11, 2001, attacks.