Elections workers in North Carolina say the voting is going smoothly with heavy turnouts, as voters in the Tarheel state and the Hoosier state of Indiana add their jigsaw pieces to the puzzle leading to the Democratic nomination for President. Barack Obama and Hillary Clinton agree the races will be close, and neither one is offering any bold predictions of a stunning victory.

Obama has led in the polls in both states, and holds onto a delegate lead of 1,746 to 1,611 over challenger Clinton. These primaries, more than the controversy over statements from Rev. Jeremiah Wright, have focused on the campaign chatter over Sen. Clinton's call for a summertime suspension of the federal gasoline tax. Obama has ridiculed the proposal as a stunt from Washington that would only save Americans 28 cents a day, and would cost jobs. Both rivals went at each other with television commercials and personal campaign time on the issue.

When the polls close tonight, the chase is on for 115 delegates in North Carolina, and another 72 in Indiana. Political analysts including Jeff Greenfield of CBS News agree, if Barack Obama wins both states tonight, there will be incredible pressure for Hillary Clinton to end her campaign now.