Obama Feels the Momentum in Dallas

This is what momentum looks like. The line outside Reunion Arena in Dallas started forming at 4 a.m. on Wednesday, the day after Obama's latest blowout victories in Wisconsin and Hawaii. Among the thousands of supporters stretching through the concrete walkways around the arena: a cluster of young Muslim women wearing headscarves just a few paces away from some troops in desert camouflage.

By the time the rally began at noon, the raucous crowd of around 18,000 inside was in a party mood. As Sam and Dave's signature song played over the sound system, a large group of supporters changed the lyrics to "Hold On, Obama's Coming." One wore a T-shirt saying "I'm Barack Obama." Another one showed three pictures: JFK, MLK and Barack Obama.

Obama's warm-up acts were just as exuberant. Dallas mayor Ron Kirk told the crowd that the candidate was suffering from the flu and recounted a conversation about Obama's similarly huge rally in Houston the night before. How, Kirk wondered, did Obama deliver such a spirited speech when he was so sick? "It was the crowd. They lifted me," Obama told Kirk. "Their enthusiasm." At which point 18,000 Dallas fans started chanting O-ba-ma.

Behind the scenes Obama's aides remain as cautious as they have been since New Hampshire's surprise defeat. They may have a national lead of 14 points over Hillary Clinton, according to the latest Reuters/Zogby poll. (That same poll gives Obama a seven-point lead over John McCain, while Clinton trails the presumptive GOP nominee by 12 points.) And they may have extended a lead among pledged delegates that amounts to more than 10 percent above Clinton's tally—a lead that Obama's aides believe is almost unbeatable in the primary and caucus contests that remain.

But they are still prepared for a tough and protracted struggle with the Clinton campaign. First there are two high-profile debates, starting in Texas on Thursday, which could potentially trip up their candidate. Obama is spending longer prepping for Thursday's debate than any other recent matchup. Obama's aides are also concerned by reports of heavy spending by a 527 group on behalf of Clinton in Ohio and Texas.

Beyond the next states, the Obama strategy looks to the contest for the superdelegate votes that will ultimately clinch the Democratic nomination. On that battlefield the Obama camp is encouraged by its string of 10 straight wins and the bump in the polls that has followed. "I think it's becoming increasingly clear that there's a big difference between what Senator Obama is able to do in a general election and what Hillary Clinton will do," campaign manager David Plouffe told reporters on Wednesday. "Whether it's pledged delegates or some evaluation of who would be the stronger general election candidate, we win convincingly on both scores." Nevertheless, that strategy envisions Obama fighting a two-front battle: against Clinton in the remaining primaries and against John McCain in a general election that has already begun.

Obama, struggling with a head cold that forced him to blow his nose in midspeech, tried to deliver a punch against both rivals in Dallas. "Today Senator Clinton told us that there's a choice in this race, and you know that I couldn't agree with her more," Obama said. "But contrary to what she's been saying, it's not a choice between speeches and solutions. It's a choice between a politics that offers more of the same divisions and distractions that didn't work in South Carolina and didn't work in Wisconsin and will not work in Texas, or a new politics of common sense, of common purpose, of shared sacrifice and shared prosperity. It's a choice between having a debate with John McCain about who has the most experience in Washington or having a debate about who is most likely to change Washington. Because that's a debate we can win."