Four years after a historic victory driven by lofty promises of hope and change, CBS News projects that a battle-hardened President Obama will win re-election with a very different message: We've made progress, but there's still a long way to go.

In the end, an election many expected to come down to the wire ended early. While Mr. Obama lost states he won four years ago, including Indiana and North Carolina, his Midwestern firewall of Ohio, Wisconsin and Iowa is projected to have held. The president was buoyed in Ohio by his action to use federal dollars to bail out the auto industry, while union households helped power him in Wisconsin. Pennsylvania's 20 electoral votes, where Republican nominee Mitt Romney made a late run in hopes of expanding the electoral map, ended up being projected to go to the president early in the evening.

One by one, projections showed battleground states falling to Mr. Obama throughout Tuesday night: New Hampshire, Iowa, Nevada, Colorado. It was enough to put him over the top even without the hard-fought battlegrounds of Virginia and Florida, where voters were lined up long after polls closed to decide close contests. (CBS News has not yet projected a winner in either state.)

After CBS News and other media outlets called the race after Mr. Obama was projected the winner in Ohio, a group of about 1,000 young people gathered in Lafayette Park, near the White House, to celebrate. In the president's home base of Chicago, Obama supporters waved flags, danced and hugged, some breaking down into tears; in Romney's home state of Boston, the GOP nominee's supporters stood shell-shocked and silent as they processed the news.

Romney has not conceded the presidential race. A source close to the Romney campaign says the Romney campaign is not giving up on Ohio, though a number of media outlets have called the state -- and thus the race -- for Mr. Obama. With 82 percent of the vote tallied, Mr. Obama held a very narrow lead.

The good news for Republicans on Tuesday: As expected, they are projected to hold onto the House of Representatives. But the Senate, which one year ago looked very likely to fall into Republican hands, was projected to stay with the Democrats - thanks in part to missteps by Republicans in Missouri and Indiana, whose controversial comments concerning rape helped vulnerable Democrats triumph.

It adds up to an election set to be remembered for maintaining the status quo. After an oft-nasty battle in which the campaigns and outside groups are projected to have spent a record-breaking $6 billion, Washington is poised to look the same way it has for the past two years: With Democrats in control of the Senate, Republicans in control of the House, and Mr. Obama in the Oval Office.

The CBS News exit poll showed Mr. Obama's victory was attributable to a double-digit advantage among women as well as huge advantages among young, urban and minority voters. (Romney led among married women, but unmarried women broke overwhelmingly to the president.) It was enough to overcome Romney's advantage among white, male, and older voters, as well as rural voters and those with high incomes.