Barack Obama may still be stumping in primary states, but his campaign is shifting full gear into general election mode.

With an end to the Democratic primary race in sight, the Illinois senator spent his Saturday in Oregon making nice with party rival Hillary Clinton and vilifying John McCain, the presumptive GOP nominee.

His campaign also announced that when Oregon holds its primary Tuesday -- a contest Obama is favored to win -- he will be elsewhere. Instead of celebrating in the Beaver State, he and his wife, Michelle, plan to hold a rally in Des Moines, Iowa, territory his aides described as "a critical general election state that Democrats must win in November."

Obama's coming campaign schedule and talking points over the past few days are casting an aura of inevitability over his campaign -- the aura that once belonged to Clinton.

The Illinois senator continued his three-day fight with McCain and President Bush over foreign policy Saturday and took shots at McCain on just about every hot-button campaign issue.

On the environment: "John McCain ... his big strategy is to do more drilling and to have a gas tax holiday for three months. That's a phony solution."

On Social Security: "John McCain doesn't have a plan in terms of helping people retire."

On college tuition: "This is not something that he thinks necessarily is a priority."

On health care: "He wants to give you the failed Bush health care policies for another four years."

Though health care has been one of the few policy issues that separate Obama and Clinton in the Democratic race -- Clinton wants to enforce a mandate for coverage, Obama doesn't -- Obama made a point Saturday of saying "the differences between Democrats on this issue pale in comparison with the differences we have with John McCain."

The foreign policy fight began when President Bush criticized politicians who would negotiate with terrorists in an address Thursday to the Israeli Knesset. Obama, who has said he would meet unconditionally with the leaders of state sponsors of terrorism like Iran, took it as a personal insult. After Democrats lunged at Bush for the remarks, Obama and McCain traded heated words on Friday.

Obama brought this issue up again Saturday.

"That's pretty appalling. ... A president as a general rule does not use a foreign country to make political attacks," Obama said. "But more importantly what it also made clear is the kind of debate, the real choice that we are going to be facing in November, a choice between the exact same policies we've had for the last eight years or real change in Washington."

McCain spokesman Tucker Bounds responded that Obama was "missing the point," and that the problem was his willingness to meet "unconditionally."

"Barack Obama's pledge to unconditionally bring Mahmoud Ahmadinejad to the world stage isn't new politics. It's incredibly weak judgment and reveals why Americans will elect John McCain's record of experience and tested leadership," he said.

Scrambling to stay in the spotlight is Clinton, who is proceeding as though the nomination still is within her grasp. She began a multi-day swing through Kentucky on Saturday with a tour of the famous distillery in Loretto, where its first bottle of bourbon whiskey was created in the 1950s.

"There are some people who have been saying for months that this is over, and every time they say it, the voters come back and say, 'Oh no it's not, we're not ready for it to be over,"' Clinton told supporters as she stood on a stage in front of a stack of whiskey barrels.

Clinton has a strong lead in polls in Kentucky, which also votes Tuesday. But Obama has racked up such a comfortable delegate lead that he likely will move within 100 delegates of clinching the nomination after Tuesday's contests.

He also continues to pick up the endorsements of superdelegates, who are party officials not bound by election results to support either candidate. Clinton had led Obama in superdelegates through most of the year, but he recently overtook her and now leads 295.5 to 274.5 -- including a superdelegate in Maryland he collected Saturday.

Overall, Obama has 1,907 delegates to Clinton's 1,718, with 2,026 delegates needed to secure the nomination.

The last Democratic primaries are June 3 in Montana and South Dakota.

Obama is heading to Florida next week -- a key general election state where he has not yet campaigned.

The Democratic National Committee stripped Florida of its delegates as punishment for moving up its primary to January, earlier than allowed by party rules.

Clinton, who did not campaign in the state either, won the Florida primary. She and Obama have been at odds over seating the state's delegation at the national convention in Denver in August.

Both candidates were distracted Saturday by news that Sen. Ted Kennedy, one of Obama's biggest backers, was hospitalized. Obama and Clinton both expressed their concern for his health, but the Massachusetts senator's condition was reportedly improving in the late afternoon after he was initially taken to the hospital suffering seizures.

FOX News' Aaron Bruns and Bonney Kapp and The Associated Press contributed to this report.