WASHINGTON (AP) -- Barack Obama has built a commanding lead, capturing another sought-after prize.
He wins Ohio and its 20 electoral votes, giving the Democrat a total of 195 to John McCain's 70. Obama needs 270 to clinch the nomination.
He'd earlier won in neighboring Pennsylvania. Both states were seen as key to McCain's victory chances.
Obama also swept the states in the East and Midwest that traditionally go blue.
McCain's latest wins are in Kansas, North Dakota, Arkansas, Alabama and Louisiana, with 33 electoral votes in all.
Democrats have picked up Republican Senate seats in Virginia, North Carolina, New Hampshire and New Mexico. But Senate Republican leader Mitch McConnell has won re-election to his Senate seat in Kentucky.
Republicans Jeff Sessions in Alabama and Pat Roberts in Kansas were also re-elected.