An activist group of doctors is running two radio ads asking Utahns to tell Sen. Bob Bennett to vote against spending on a new Bush administration nuclear weapons program.

But Bennett, R-Utah, has already introduced legislation aimed at limiting any renewed nuclear testing at the Nevada Test Site.

And Bennett spokeswoman Mary Jane Collipriest says the senator has supported the new "bunker-busting" weapons program because he believes no new nuclear testing will be conducted.

"You don't have to set off a nuclear warhead to test it; there are computer simulations" that are adequate, she said. And Bennett's bill will actually ensure that no new above-ground testing goes forward, she added.

Physicians For Social Responsibility are running radio ads in Utah and Virginia aimed at U.S. senators it hopes will vote against the so-called "bunker busting" spending in an upcoming vote on an energy and water budget bill. Bennett has said before he supports studying and initial planning for the new weapons program, which Bush says could be used against hardened, deep underground bunkers, such as those used by former Iraqi leader Saddam Hussein.

Bennett faces former Democratic Utah attorney general Paul Van Dam in November's election. Van Dam opposes the new weapons program, saying, as some other Utah Democrats have, that even studying the issue is a step down the road toward renewing America's underground nuclear testing program, which ended in the early 1992.

The 30-second radio ad says Bennett's vote will be key in "a closely divided Senate . . . Tell him to vote no on new nuclear weapons and any return to nuclear tests," it says.

A 60-second ad says Bennett's vote could be the difference between "a healthy and serene Utah for our families, or a return to the dangerous days of nuclear blasts."