U.S. Sen. Saxby Chambliss said he's told President Bush that vetoing the $300 billion farm bill would be a "huge mistake" that could hurt Republican presidential candidate John McCain in November.

"He and I have had a couple personal conversations about that. I think it's a huge mistake for him, politically and otherwise," said Chambliss, a Republican who himself faces re-election this year.

Chambliss said he pointed out to Bush that the states in the South and West that gave him his strongest support all had agricultural economies.

"These are people that want to vote for John McCain. If they get turned off by Republicans, it's going to make it tough," Chambliss told reporters after a speech to the state GOP convention.

The House and Senate both passed the massive bipartisan bill this week by veto-proof margins. Both Chambliss and U.S. Sen. Johnny Isakson have promised to help override the veto that Bush has promised.

In the House, five of Georgia's seven Republican House members — some of whom will address the convention today — voted against the bill. And some conservative Republicans in Georgia have balked at the spending.

Last year, Chambliss faced the state GOP convention just as an immigration bill was unveiled. He and Isakson had participated in the negotiations, and Chambliss received a round of boos from delegates.

On Friday, at a sparsely attended afternoon session, Chambliss took no chance that the farm bill might also provoke the crowd's displeasure. He made no mention of it or of immigration.

Instead, Chambliss warned the GOP base that its support of McCain was crucial for the sake of the U.S. military, the war in Iraq and the appointment of future U.S. Supreme Court justices.

He called his own re-election, for which he has amassed $3.6 million in cash on hand, as "critically important" in order to keep Democrats short of the 60 votes they need in the Senate to cut off filibusters.

"Today, because we have 49 Republicans, we're able to take bad legislation and either shape it, and make it better, or kill it," Chambliss said. "But if we get our number down to where we don't have those 41 votes we need on a regular basis, then this country will be worse off, I promise you."

Only afterwards, in a session with reporters, did Chambliss address Bush's criticism of the farm bill, including Bush's contention that the legislation awards subsidies to high-income farmers.

"That's ridiculous. It really is. I get upset when some of my colleagues say, well we're giving money to rich farmers. We're not doing that," Chambliss said.

The former chairman of the Senate Agriculture Committee pointed out that the last farm bill passed in 2002 had no income limit on participation. The new limit would cut off subsidies from farmers with incomes of $750,000 and more.

Chambliss pointed out that 70 percent of the bill's spending goes toward food stamps, school lunches and food banks — which benefit one in every 10 Georgians.

The senator said one victory in the bill for conservatives is a reform of the federal endangered species act. For the first time, the legislation gives landowners tax credits for property taken out of production to guard the habitat of protected animals.