Before Obama secured enough delegates in June to win the Democratic nomination, he and his likely Republican challenger, Sen. John McCain of Arizona, each averaged about 45 percent in the Gallup Poll Daily tracking, pollsters said Wednesday. Since then, Obama picked up an average of 3 percentage points -- 46 percent to 43 percent -- in states seen as traditionally Democratic or Republican and swing states.

While Obama made slight inroads -- 3 points -- in blue (Democratic) and red (GOP) states, he showed greater gains in the competitive states, where his lead expand by 6 points, the Princeton, N.J., polling firm said.

Since early June, Obama has averaged a 16-point lead over McCain in blue states and an 8-point lead in swing states, Gallup said. He trails McCain by an average of 10 points in red states.

Results for June 2-July 20 survey are based on telephone interviews with 39,603 registered voters, including 14,548 in red states, 13,311 in blue states and 11,744 in purple states. The total sample's margin of error is plus or minus 1 percentage point.