Sen. Barack Obama went a long way toward wrapping up the Democratic nomination for president Tuesday night.
By winning big in North Carolina and only narrowly losing in Indiana, Obama showed his resilience. He bounced back from his loss to Sen. Hillary Clinton in Pennsylvania, boosting his lead in the popular vote and in pledged delegates.
Clinton has nearly run out of time and money. Since winning Pennsylvania, she has lent her campaign $6.4 million. She doesn't have to drop out of the race, as party elder George McGovern urged yesterday. But the will of the voters is becoming more clear with each passing day.
With only six primaries remaining, Obama leads Clinton by about 155 pledged delegates. In the final six contests combined, only 217 delegates are at stake. The math makes it virtually impossible for her to overtake Obama, either in pledged delegates or in the popular vote.
So it's hard to take seriously Clinton's rallying cry after eking out the win in Indiana: "Full speed on to the White House!" She's in second place, and has been stuck in that position consistently. That reality hasn't changed in nearly three months of primaries from coast to coast.
More than ever, Clinton seems to be pinning her dwindling hopes on lobbying uncommitted Democratic superdelegates to support her. But those superdelegates - mostly elected party officials - know the risk in offending all of the new voters that Obama has generated.
Even if Obama can't reach the magic number of 2,025 delegates, he is leading "by any practical test," as McGovern said.
Some Democrats fret that this prolonged primary has hurt their party's chances of winning the White House in November. If anything, this tough campaign has seasoned Obama.
He rose to the challenge of the controversy over his former pastor, the Rev. Jeremiah A. Wright, and has maintained his lead over a formidable opponent. He resisted the temptation to pander to voters with the promise of a "gas-tax holiday," and it didn't hurt him.
One of the greatest challenges ahead for Obama will be to attract more support from working-class white voters - the so-called "Reagan Democrats." He did slightly better in union households in Indiana (46 percent) than he did in Pennsylvania (41 percent). And he performed better with voters earning less than $50,000 a year in North Carolina (60 percent) and Indiana (50 percent) than he did in Pennsylvania (46 percent).
Clinton may fight on. She may feel an obligation to supporters. But the outcome appears clear.