What happened
New polls show show Barack Obama’s support has grown broader since his string of recent Democratic primary victories. Most Democrats think he’s the candidate most likely to beat Republican John McCain, and think Obama is much better than rival Hillary Clinton in uniting and inspiring Americans. But Clinton is still seen by more Democrats as the one prepared to be president. (The New York Times, free registration)

What the commentators said
It’s easy to peg the reason for Obama’s momentum, said Alec MacGillis in The Washington Post (free registration). Historians agree that no presidential candidate has “been propelled so much by the force of words” since Franklin D. Roosevelt’s “whistle-stop tour” and radio addresses. But his reliance on speechmaking has created a new vulnerability -- Clinton is trying to gain traction by depicting Obama as a “glib salesman,” and presumptive GOP nominee McCain is warning Americans not to be “deceived by an eloquent but empty call for change.”

It’s anybody’s guess why McCain has “joined the fray,” said Stephen F. Hayes in The Wall Street Journal. Clinton has been saying Obama lacks “substance” for weeks, and the complaint is clearly not “working.” It’s wrong to say that because Obama “gives a good speech he cannot do substance,” and if the GOP doesn’t figure that out, quickly, they’ll make the same mistake the Democrats did when they failed to take Ronald Reagan seriously.

Obama’s speeches have substance, said Michael Barone in The Washington Times, but it’s not “very interesting.” All he does is cut and paste old Democratic platform planks into “the unspecific ode to hope that has enchanted so many voters,” and, as Robert Samuelson wrote in The Washington Post last week, his “standard goody-bag politics” don’t live up to his high-flying oratory.

“In emphasizing newness,” said John B. Judis in The New Republic Online, “Obama is actually voicing a very old theme. When he speaks of change, hope, and choosing the future over the past, when he pledges to end racial divisions or attacks special interests, Obama is striking chords that resonate deeply in the American psyche. He is making a promise to voters that is as old as the country itself: to wipe clean the slate of history and begin again from scratch.”