Clinton spoke to supporters in Indianapolis, while awaiting for the Indiana primary race to be called.

With 91 percent of the state's precincts counted, Clinton led Obama 51 percent to 49 percent, with about 20,000 votes separating the two U.S. senators, CNN reported. Votes were reported late coming in from Lake County in northwestern Indiana near Chicago.

"I need your help to continue our journey," the New York senator said, with her daughter Chelsea and husband, former president Bill Clinton, standing behind her.

"This has always been your campaign and this is your victory because your support has meant the difference between winning and losing," Clinton said. "And we can only keep winning if we're able to keep competing against an opponent who does outspend us massively. So I hope you will go to hillaryclinton.com and support our campaign."

Clinton also said if Obama is the nominee she will support his run against Republican Sen. John McCain of Arizona.

"I have said on many occasions that no matter what happens, I will work for the nominee of the Democratic Party because we must win in November. And I know Senator Obama feels the same way because we have been on this campaign trail now for a long time," she said.