Senator Barack Obama continues to lead in the delegate count and in the total number of popular votes won in the battle for the Democratic Party's presidential nomination.

But Senator Hillary Clinton is counting on a victory in Pennsylvania to keep her in the race, perhaps all the way to the Democratic National Convention in late August.

"I have consistently made the case that I can win, because I believe I can win," she said. "You know, sometimes people draw the conclusion that I am saying somebody else cannot win. I can win. I know I can win. That is why I do this every day."

Clinton and her campaign supporters have pounded Obama for his description of small town Pennsylvania voters as bitter from economic struggles and clinging to guns and religion.

Obama has said he regrets his choice of words, but has stood by his main point that voters have grown weary of empty economic promises from both major political parties.

Some political analysts believe the Clinton attacks on Obama could give Republicans plenty of ammunition for the general-election campaign should Obama become the Democratic nominee.