Barack Obama's insurgency has entered the phase of the general offensive. It began last year, perhaps earlier, with foolish audacity and serious low-visibility organizing of both people and money. It surprised the overconfident incumbent machine with a peaceful uprising in Iowa, suffered a sudden counter-attack in New Hampshire, but kept rolling up wins at the popular periphery, survived against the heaviest establishment blows on Super Tuesday, and now is poised to compete with concentrated force against the dwindling citadels of the opposition [Texas and Ohio], before swarming through the last primaries of Rhode Island [21 pledged delegates], Vermont [12], Wyoming [12], Mississippi [33], Pennsylvania [151], Guam [3], Indiana [66], West Virginia [26], North Carolina [91], Oregon [48], Puerto Rico [55], Oregon [48], Montana [15], South Dakota [9]. There are 564 pledged delegates up for grabs in those last 15 contests alone, and most if not all lean already towards Obama.

What about Hillary Clinton's "firewall" states of Ohio and Texas? When the balance of forces shifts in a competition, when the general offensive is on, little can hold it back. Wavering voters shift their allegiances. Donors defect. The calculation of electability shifts. The old leadership is staggered, off balance, the ground collapsing under their feet. Even if Clinton wins in Ohio and Texas, the margins will not be enough to block his momentum.

What about the super-delegates? Won't the party establishment become Clinton's safety net? Not in the face of the running tide, not a chance.

Won't this go all the way to the August Democratic convention? The pressure to turn the Democratic forces towards the November general election, towards responding to John McCain, will become too overwhelming to resist.

Obama has run a brilliant campaign, unprecedented for a first run for president. His greatest challenge at this point is not the faltering Clinton campaign, but the difficulties of transitioning to front-runner status without stumbling. It's not over, but it's his to lose.

[more to come]