FAYETTEVILLE, North Carolina (AFP) - Democrat Barack Obama on Sunday pursued his audacious hunt for votes in America's conservative heartland after rallying monster crowds in the Republican "red" state of Missouri with a rousing call for change. Just over a fortnight before the Nov 4 election, the White House hopeful was to campaign in North Carolina, which last voted for a Democratic presidential contender in 1976 but is now a toss-up state. And Obama's camp was hoping for a landmark endorsement as NBC prepared to air an interview on its Sunday politics show "Meet the Press" with former secretary of state Colin Powell, a Republican military grandee. For the liberal left, Powell was tarnished by his role in promoting the US invasion of Iraq. But it would be a stern slap to Republican John McCain's candidacy if the former chairman of the joint chiefs of staff backed Obama. McCain, fighting a rearguard offensive as his poll numbers sag, insisted that Obama's economic plan would "kill" job creation as the United States weathers its worst financial crisis in decades. The day's first crowd in St Louis numbered at least 100,000, Obama's biggest yet in the United States. An evening rally in Kansas City, Missouri's other big metropolis, attracted more than 75,000 supporters. The 47-year-old candidate bidding to be the nation's first black president said the enormous turnouts were proof "the winds are blowing for change across America," as he bids to flip red states into Democratic "blue." The Illinois senator was ahead of McCain by 50pc to 42 percent in Saturday's Gallup national tracking poll. In the Rasmussen tracking poll, the Democrat was up 50 percent to 45. But Obama reiterated his message of recent days that supporters should not get "cocky" as he headed to North Carolina and then Florida on Monday for a joint rally with his vanquished primary rival, Hillary Clinton. "Democrats have a way of snatching defeat from the jaws from victory," he said. "We've got to keep running through that finish line." At his own rallies in North Carolina and Virginia, another red state now very much in play, McCain Saturday once again invoked Ohio plumber Samuel "Joe" Wurzelbacher, a new hero to conservatives after challenging Obama on taxes. "Joe's dream is to own a small business that will create jobs in his community, and the attacks on him are an attack on small businesses all over the country," McCain said as a harsh media spotlight turns on Wurzelbacher. Joe the Plumber and low taxes have become McCain's latest campaign motifs as the Arizona senator, 72, vies to resuscitate his flagging White House hopes on the final stretch to the election. Meanwhile, Republican White House candidate John McCain, who has seen his standing in the polls sink in recent weeks, on Sunday evoked the prospect of his own defeat but said he would not be "feeling sorry for himself" if he lost. Asked on Fox News Sunday whether he had considered the possibility of losing on November 4 to his Democratic rival Barack Obama, McCain said "Oh sure. I mean, I don't dwell on it. "I'm the luckiest guy you ever interviewed.... Don't feel sorry for John McCain, and John McCain will be concentrating on not feeling sorry for himself." Meanwhile,Democrat Barack Obama more than doubled his fundraising record with a mammoth September haul of more than 150 million dollars for the final stretch of his White House campaign, aides said Sunday. The extravaganza of giving enabled Obama to demolish his previous one-month record of 66 million dollars in August, which had already set him fair to hit Republican John McCain hard in the closing months of their race. "Because of your great generosity we had a record-breaking September," Obama's campaign manager David Plouffe said as he prepared to file the month's fundraising figures with the Federal Election Commission. Aides said Obama now has more than 3.1 million donors. The campaign added 632,000 members to its army of grassroots donors last month who each gave an average of 86 dollars.