Democrats Barack Obama and Hillary Clinton wooed working-class voters in Indiana and North Carolina today in a late push for support on the eve of critical presidential showdowns in the two states.
The senators, embroiled in a grueling nominating struggle that has split the party, started early on a long day of campaigning that will take them to both states voting in tomorrow's contests.
Clinton renewed her criticism of Obama for opposing her proposal to lift the federal gasoline tax for the summer, which Obama and many economists have rejected as political pandering. Clinton has used the issue to emphasise her support for workers struggling with record petrol prices in a faltering economy.
"Senator Obama doesn't want to do anything," Clinton, a New York senator, told a rally at a community college in Greenville, North Carolina.
"You don't hire a president to make speeches. You hire a president to solve problems."
Obama, an Illinois senator, made an early-morning visit to a construction site in Evansville, Indiana, where he talked to workers about jobs and high petrol costs. During an appearance on NBC's "Today" show, he said the gas tax holiday was a dishonest approach to a real problem.
"There is not a single economist or editorial that I've read that says that this is a good idea, and the reason is, is because it's not being honest with the American people," Obama said.
"People don't need symbolic relief, they need real relief."
Indiana and North Carolina, with a combined 187 delegates to the August nominating convention at stake, are the biggest prizes remaining in a state-by-state Democratic race. There will then be only six contests left.
Obama leads Clinton in the race for the 2,025 delegates needed to win the nomination to face Republican John McCain in November's presidential election.
Voting in the Tuesday elections ends in Indiana at 11pm Irish time and in North Carolina at 11.30pm Irish time, with results expected soon after.
Wins for Obama in both states would effectively end Clinton's chances of overtaking him in either delegates or popular votes cast in the state-by-state battle.
But a sweep of the two states by Clinton would fan doubts about Obama's electability and prolong a rough patch where he has been on the defensive over a big loss in Pennsylvania and his relationship with his controversial former pastor Rev. Jeremiah Wright.
Obama leads in polls in North Carolina, although his once double-digit advantage over Clinton has shrunk to single digits. The two are running close in Indiana, where most polls show Clinton with a slight lead.
Neither candidate will win enough delegates before the voting ends on June 3 to clinch the nomination, leaving the decision to nearly 800 superdelegates -- elected officials and party insiders -- who are free to back any candidate.
A split decision tomorrow would leave the race largely unchanged, with the candidates trying to convince the superdelegates they would be the best Democrat to take on McCain.