Barack Obama 49.4
John McCain 48.6
Barack Obama has a very small lead in Missouri that suffice it to say is within the poll's margin of error.
If he could keep his deficit among white voters in the state within single digits he would be in good shape to win it, but he currently trails 55-43 with that demographic. His 93-7 advantage among black voters evens that out, which means that the winner in Missouri could end up having a lot to do with the relative proportions of black and white voters within the electorate.
The candidates are knotted among independents voters, 48-48. McCain is pulling slightly more (91%) of his party's vote than Obama is (88%) but that's evened out by the slight Democratic identification edge in the state.
Obama has a dominant 61-35 lead with voters under 30 while trailing in every other age group. His ability to ensure those folks actually get out and cast their ballots may determine who takes Missouri.
Full results here.