The focus on the stump Saturday for both Obama and McCain continued to be taxes, and the candidates traded sharp criticisms of each other's plans.
More from the AP:
McCain, trailing in the polls, fired the first volley, likening his rival to the socialist leaders of Europe and saying he wanted to "convert the IRS into a giant welfare agency, redistributing massive amounts of wealth at the direction of politicians in Washington."
McCain added, "Raising taxes on some in order to give checks to others is not a tax cut; it's just another government giveaway."
Obama responded a few hours later in appearance before an enormous crowd, saying his Republican rival "wants to cut taxes for the same people who have already been making out like bandits, in some cases literally."
"John McCain is so out of touch with the struggles you are facing that he must be the first politician in history to call a tax cut for working people 'welfare,'" Obama said.
The Wall Street Journal has more details:
Barack Obama attracted 100,000 people at a Saturday rally here, his biggest crowd ever at a U.S. event.
The crowd assembled under the Gateway Arch on a sunny Saturday afternoon to hear Obama speak about taxes and slam the Republicans on economic issues.
Lt. Samuel Dotson of the St. Louis Police Department confirmed the number of attendees piled into the grassy lawn by the Mississippi River.
To be sure, big crowds don't always signal a big turnout on Election Day. But Obama's ability to draw his largest audience yet in a typically red state that just weeks ago looked out of reach, could signal a changing electoral map.
For months Missouri polls put Obama as much as ten percentage points behind Republican John McCain. It was widely believed that McCain's pick of Alaska Gov. Sarah Palin as his running mate would have won over the state's conservatives and boosted his chances there. So far, that hasn't happened.
A Rasmussen poll released on Friday shows Obama leading in Missouri 52% to 46% for McCain.