obama_mccain_3.jpgWASHINGTON (AP) _ Democrat Barack Obama fired off a broadside linking likely Republican presidential nominee John McCain to U.S. President George W. Bush's unpopular economic policies, a tactic he is likely to rely on to woo voters worried about economic uncertainty as he looks toward his general election strategy.

Obama was campaigning before Tuesday's primaries in Oregon and Kentucky, votes that are expected to put him less than 100 delegates away from reaching the total 2,026 needed to secure his party's nomination after an epic battle with Hillary Rodham Clinton.

Obama has begun casting himself as the inevitable nominee, lumping McCain in with the unpopular Bush as he starts turning toward the November election campaign. He has scheduled appearances later this week in Iowa and Florida, two key swing states that have already held their primaries.

Obama, who is bidding to be the first black U.S. president, has also started tailoring his message to such voting blocs as senior citizens and working-class whites that favored Clinton in their nomination contest and will be important in the November election. The economy has quickly outpaced Iraq as one of the major issues of the presidential campaign.

On Sunday, Obama tried to undermine McCain's appeal to fellow senior citizens by turning to such issues. He said during a stop in Oregon that the Republican candidate would threaten government retirement benefits because he supports Bush's policy of privatizing the program.

“Let me be clear, privatizing Social Security was a bad idea when George W. Bush proposed it, it's a bad idea today,'' Obama said. “That's why I stood up against this plan in the Senate and that's why I won't stand for it as president.''

Bush proposed a Social Security plan in 2005 that focused on creating private accounts for younger workers, but it never came up for a vote in Congress. Democrats strongly opposed the idea and few Republicans embraced it.

Obama said McCain would push to raise the retirement age for collecting government retirement benefits or trim annual cost-of-living increases. Obama has rejected both ideas as solutions to the funding crisis projected for Social Security in favor of making higher-income workers pay more into the system.

McCain spokesman Tucker Bounds accused Obama of making “misinformed partisan attacks.''

“John McCain has been clear about his belief that we must fix Social Security for future generations and keep our promises to today's retirees, but raising taxes should not be the answer to every problem,'' Bounds said.

Meanwhile, one of McCain's key fundraisers, Thomas G. Loeffler, stepped down, marking the latest casualty of a campaign eager to stem damage caused by its ties to lobbyists. Loeffler, who runs the lobbying company The Loeffler Group, is the highest profile departure from McCain's inner circle since McCain fired his campaign manager and chief strategist last summer.

The work of lobbyists in McCain's campaign had become fodder for critics, undermining his image as a reformer who is trying to restrict the influence of special interests.

Obama flew to Montana for a day of campaigning Monday. His aides announced that he planned to hold a rally on primary night Tuesday in Iowa, where his solid win in January's leadoff caucuses propelled him to his status as the front-runner.

He held a spectacular outdoor rally Sunday at a sun-splashed scene on the banks of the Willamette River in Portland, Oregon. City fire officials estimated 65,000 packed into a riverside park with an additional 15,000 left outside.

Clinton was leading by a big margin before Kentucky, where she plans to campaign through Tuesday.

At stake Tuesday are 51 delegates in Kentucky and 52 in Oregon. After these primaries, Obama most likely will have secured the majority of pledged delegates to the Democratic National Convention who are available in all the party's primaries and caucuses, strengthening his claim to the nomination.

Clinton, whose hopes are fast fading to become the first female U.S. president, has insisted she is staying in the race until the last primaries on June 3 in Montana and South Dakota.

She is hoping for a big win in Kentucky, whose demographics resemble neighboring West Virginia, which gave a victory last week. Both states are overwhelmingly white, rural and have more residents below the poverty line and without college degrees than the national average _ the kind of working-class voters who have helped boost Clinton to victory in other states. Obama's core supporters include blacks, young voters and upper-income Democrats.

A prominent Democratic elder statesman, former New York Gov. Mario Cuomo, suggested that an Obama-Clinton ticket is the best way to bridge the divide within Democratic ranks and boost the party's chances against McCain.

“No other possible candidate has been tested the way they have,'' Cuomo said Sunday on CBS television's “Face the Nation.''

Neither candidate has ruled out a joint ticket, but both Obama and Clinton have suggested it is presumptuous to talk about a vice presidential choice while the primary battle continues.

Obama now enjoys a delegate advantage that makes it mathematically unlikely for Clinton to overtake him in the remaining five contests. Obama's overall delegate count _ including superdelegates and pledged delegates _ now totals 1,909 to Clinton's 1,721.