He said Mitt Romney was basically running on two ideas. "One, that we need to slash taxes even more for the wealthiest and most successful among us. And two, we need to eliminate any kinds of regulations, whether they're consumer regulations or worker regulations or environmental regulations that in any way impede the free market from operating however it will."
Earlier, to a larger crowd of supporters gathered in the museum rotunda under the marble gaze of Benjamin Franklin's statue, the president spoke well of Romney as a person, describing the former Massachusetts governor as "a patriotic American, and he's got a lovely family and he should be proud of his personal success. But his ideas are just retreads of things that we have tried and that failed."
The speech was the last of three Tuesday night fund-raising events the president held at the museum - which had been the site of a Romney rally with tea party members just two months ago.
Earlier in the day, Obama visited with about 130 graduates of the Science Leadership Academy, a joint venture between the school district and the Franklin Institute.
He then joined a campaign roundtable with 25 donors who had each pledged to give or raise $40,000 in return for a private chat with the president; their meeting was closed to reporters and the campaign did not disclose attendees' names.
In between events, the White House said, the president took time to head to the museum's third floor and see the exhibit of the Dead Sea Scrolls.
From there it was on to the rotunda, where Obama delivered remarks to more donors. Tickets for that event started at $250. Finally, the president spoke at a dinner (prime rib, crab cakes, and a vegetarian option) attended by 75 people - tickets starting at $10,000.
He said Republican leaders had helped drive up the government's deficit. "They ran up the tab and are trying to pass off the bill to me," he said. "Let me tell you something: The two presidents with the least growth in government spending in the modern era happen to be two Democrats, named Barack Obama and Bill Clinton. It wasn't the other guys."
A cheer went up.
Proceeds from all the events went to the Obama Victory Fund, a joint fund-raising effort of Obama for America and state and national Democratic groups.
The visit came on the day that a Quinnipiac University poll found Obama holding a steady six-point lead over Romney in Pennsylvania.
Obama's 46-to-40-percent edge among registered voters is virtually unchanged from the university's May survey, and pollsters said the president is buoyed in the Democrat-leaning state by his advantage among women and independents.
In Tuesday's poll, women backed Obama 51 percent to 36 percent in Pennsylvania, while men narrowly favored Romney, 44 percent to 40 percent. Obama is leading by 43 percent to 35 percent among independent voters, the poll finds.
But the poll also contains warning signs for Obama: He hasn't cracked 50 percent support in a series of Quinnipiac polls; his job-approval rating in this survey (46 percent) is worse than his likability rating of 77 percent. By 49 percent to 41, respondents said Romney would do better at handling the economy. Asked which man would create more jobs, 45 percent picked the Republican, to 43 percent who named Obama.
"Pennsylvanians may like the president more than Mitt Romney, but the warm-and-fuzzy feeling gives way to the cold, hard truth of a still-shaky economy," said Tim Malloy, assistant director of the university's polling institute.
Obama's visit marked the ninth weekday in the last 27 that he has been on the road raising campaign cash; he had three events in Baltimore earlier in the day.
Pennsylvania Republicans sought to "pre-but" his visit here during an afternoon conference call with reporters, centering on his comment last week that "the private sector is doing fine."
"Mr. President, we're not doing fine," said state GOP Chairman Rob Gleason. "You're not doing fine, either. It's time for you to go." Though Pennsylvania's 7.4 percent unemployment rate is lower than the national average of 8.2 percent, Gleason said that the number does not reflect huge numbers of out-of-work state residents who have given up looking for jobs.
Rep. Jim Gerlach, of the Sixth District in suburban Philadelphia, spoke of a young medical-device company he had visited Tuesday, Neuronetics, that faces a new 2.3 percent gross-receipts tax next year as part of the Obama health-care overhaul. "It's absolutely going to crush them in terms of their ability to grow," Gerlach said. "If the president is serious about jobs, he should come a few miles west of Philadelphia and speak to the medical-device manufacturers."
The industry says Pennsylvania is home to 600 companies that make medical devices, employing about 20,000 people.
The man who introduced Obama to the audience in the planetarium was one of his top local money-raisers - David L. Cohen, the executive vice president of Comcast and Ed Rendell's former mayoral chief of staff.
One Obama backer who gave generously to be with him Tuesday night was a former student of his. Center City lawyer Adam Bonin said he was a student at the University of Chicago Law School in 1996 when he took "Election Law" and "Race and the Law" courses taught by then-Professor Obama.
When he got his moment with Obama at the fund-raiser, Bonin said he deadpanned: "Mr. President, I'd like to talk about my grade." He said Obama observed, "We're both a little grayer than last time."
Contact Thomas Fitzgerald
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