President Obama attended a science fair, opened the door to arming Libyan rebels and raised $1.5 million for the Democratic Party—all in eight hours in New York City on Tuesday.

Obama’s main reason for visiting the Big Apple was two major fundraising events. But he managed to squeeze in a trip to the United Nations to dedicate a building, three interviews with network news anchors and a surprise stop at the New York City Science and Engineering Fair.

“I’ve been traveling around the country talking about how America can win the future. . . Whenever I get a chance to go to a science fair, I go,” Obama told a group of students at the event before stopping by a series of exhibits.

As expected, Libya was a major theme of the day. At a UN event to honor Ron Brown, who served as Secretary of Commerce under President Clinton until Brown died in a plane crash in 1996, Obama spoke of the importance of the international community joining together in the North African country.

In his unusual tv blitz, Obama stuck to the themes of his Monday night address. He said he wouldn’t rule in or out providing military aid to Libyan rebels. But pressed on his broader policy in the Middle East, he said decisions would be made on a country-by-country basis.

“I think it’s important not to take this particular situation and then try to project some sort of Obama doctrine that we’re going to apply in a cookie-cutter fashion across the board. Each country in this region is different,” Obama said in an NBC News interview.

Arriving Tuesday evening at Harlem’s Red Rooster for a Democratic Party dinner, the president begged off dining on a meal that included lobster salad with asparagus, braised short ribs with honey-glazed artichokes, cornbread with honey butter and sweet potato doughnuts with cinnamon and brown sugar.

But he assured the 50 donors who were there, having given $30,800 to the Democratic National Committee to have a “small dinner and discussion” with Obama as it was billed in the invitation, that it was a good thing he wouldn’t actually dine.

“That also leaves me time to actually answer your questions,” Obama said in brief remarks, before stopping at six individual tables to greet and speak to party donors. (Reporters were only allowed to see his formal speech at the fundraiser.)

Obama finished the day by attending a larger fundraising event at an arts museum in Harlem. No donation was required to attend, although Democratic officials invited people who they hope will give when Obama’s reelection campaign gets going.

“Diane Sawyer I think it was, she started listing out, well, let’s see, two wars that you’ve dealt with, a couple of earthquakes, nuclear situation in Japan, H1N1 virus, worst recession since the Great Depression. ‘No wonder you look old’ she said,” Obama told the audience. At least on camera, the ABC News anchor had listed the challenges the president faces, but not remarked on his looks.

“You look great,” someone in the audience shouted.

“No, she actually did not say, ‘no wonder you look old,” the president responded. “But I do appreciate you saying that I look great. I need encouragement too once in a while.”

The president boarded Air Force One for Washington around 10 p.m. But his day was still not done: he placed a phone call to Japanese Prime Minister Naoto Kan from the plane to discuss Japan’s recovery from the devastating earthquake and tsunami.

Obama today

Back in Washington, the president will give a major speech on energy. April is energy month at the White House, following February’s focus on innovation and education in March.