The Note: Drifting Toward Denver

April 24, 2008 -- It's Clinton vs. Math, and Obama vs. Demographics.

The good news for Sen. Barack Obama: If he needs to show that he can fight, he won't have trouble finding one.

The bad news: Once a Clinton is off the mat, there's no telling what happens next.

The good news for Sen. Hillary Clinton: She lives to fight another day (or 12).

The bad news: The battle she's fighting may already be over (and only the Democratic Party stands to lose more than she does).

If Pennsylvania changed nothing else, it shifted a psychological burden from Clinton to Obama; instead of asking why Clinton won't drop out, we're asking why Obama can't force her out.

The calls for a quick exit have been silenced, superdelegates have been (mostly) frozen -- and Obama, D-Ill., has at least two more weeks of questions to face about his candidacy, even while Clinton, D-N.Y., can focus making her message work in Indiana (while trying her best to reinvent mathematics).

Flood forestalled: The day after PA brought Obama two new superdelegates, and Clinton one. Obama holds a 138-delegate edge, per ABC's delegate scorecard, and stands 301 delegates away from the finish line. (Clinton is back to even on superdelegates since Feb. 5; Obama has netted

Buckle up: "Clinton's victory in Pennsylvania on Tuesday stilled talk that she should consider quitting the race before the end of the primaries because of Obama's significant advantage in pledged delegates," Dan Balz and Perry Bacon Jr. write in The Washington Post.

Said former DNC chairman Don Fowler, on the undecided superdelegates: "The ones I know are quite content to let things drift along."

"Hillary Rodham Clinton's Pennsylvania win has bought her time -- but not much -- to make her case to the Democratic Party's superdelegates," per the Los Angeles Times.

"Interviews with dozens of superdelegates across the country Wednesday turned up a growing acceptance that the intramural contest between Sen. Clinton of New York and Sen. Barack Obama of Illinois will probably continue for six more weeks."

The results have allowed Clinton to bring her central argument to the surface in a more delicate manner than she's been able to previously: She doesn't have to say Obama can't win, since there are numbers to speak to that.

Obama's "second consecutive lopsided loss in a critical swing state has exposed soft spots," per ABC News.

"He's had persistent problems in winning working-class, less-educated, whites -- and Pennsylvania accentuated his seeming inability to connect with those voters. While Obama remains the prohibitive frontrunner -- with an effectively insurmountable lead in elected delegates -- those potential weaknesses among key demographic groups are fueling a fierce argument inside the Democratic Party over Obama's ability to win a general election."

"Sen. Obama's defeat in Pennsylvania by nearly 10 percentage points, on top of a similar loss to the New York senator in Ohio last month, reflected poor showings among white working-class voters and Roman Catholics -- two key voting blocs in a crucial state," Jackie Calmes and Mary Jacoby write in The Wall Street Journal.

"Some Democratic officials say that could bode badly for a race against Republican Sen. John McCain, who has strong appeal to some independent and crossover voters."

Clinton's win brings new questions about race. "The Illinois senator won only 38 percent of the white vote in Pennsylvania on Tuesday, a big part of the reason he lost the state," McClatchy's Stephen Thomma writes. "Of the 30 states so far where voters were interviewed as they left polling places, Obama won the white vote in just seven, including his home state of Illinois."

"Why has he been unable to win over enough working-class and white voters to wrap up the Democratic nomination?" asks Adam Nagourney in The New York Times. "Lurking behind that question is another: Is the Democratic Party hesitating about race as it moves to the brink of nominating an African-American to be president?"

The New York Daily News' Michael Saul calls it the " 'bitter' aftertaste": "Blue-collar whites shunned Obama on Tuesday in the Keystone State, raising questions about his ability to attract the key voting bloc in a general election matchup with John McCain."

Bill Clinton is jumping on this theme -- keying off comments David Axelrod made on NPR Wednesday.

"Today her opponent's campaign strategist said, well, we don't really need these working class people to win, half the time they vote for Republicans anyways," the former president said in North Carolina, per ABC's Sarah Amos.

"And I will tell you something, America needs you to win, and therefore Hillary wants your support, and I hope you will help her in this primary in North Carolina."

McCain campaign manager Rick Davis likes what he sees: "The cracks in Obama's Democratic coalition in Pennsylvania mirror what we saw in Ohio, and those cracks could have implications in November," Davis writes in a memo.

The bottom line: Obama hasn't answered the questions that have swirled around his candidacy. "The data from last night suggests that voters believe that Hillary Clinton's argument about Barack Obama's general election viability will remain valid until Obama renders it invalid," The Atlantic's Marc Ambinder writes.

This is not the image Obama needs: "If you look at Obama's vote in Pennsylvania, you begin to see the outlines of the old George McGovern coalition that haunted the Democrats during the '70s and '80s, led by college students and minorities," John B. Judis writes in The New Republic. "Its ideology is very liberal. Whereas in the first primaries and caucuses, Obama benefited from being seen as middle-of-the-road or even conservative, he is now receiving his strongest support from voters who see themselves as 'very liberal.' "

But numbers can mislead: "For all of her primary night celebrations in the populous states, exit polling and independent political analysts offer evidence that Mr. Obama could do just as well as Mrs. Clinton among blocs of voters with whom he now runs behind," Patrick Healy writes in The New York Times.

"Obama advisers say he also appears well-positioned to win swing states and believe he would have a strong shot at winning traditional Republican states like Virginia."

And numbers are stubborn: "If this contest were still at the point where momentum, symbolism, and reading tea leaves mattered, Clinton would be in pretty good shape," writes National Journal's Charlie Cook. "Clinton is winning in big, important places, but it's happening about three months too late."