The crowd at Hillary Clinton's election night party seemed listless and exhausted but at least one man was scurrying around with an air of urgency.

Tom Williams, selling official "Hoosiers for Hillary" T-shirts was desperately trying to shift his surplus stock. "This costs $10 but you can have it for five," he said. "Right now it's a devalued piece of merchandise."

Just how devalued was a matter of some debate. The candidate herself had arrived in a 12-car cavalcade shortly after 9.30pm, knowing she had lost North Carolina by a wide margin but apparently heading for a narrow win in Indiana.

Almost an hour later she had still not appeared as news channels stubbornly refused to declare her the victor. Some of her supporters were wilting. Steve Hantz, 43, was even lying down on the floor. "I'm trying to save energy, there's not a lot of it around at the moment." Susie Bowen, 53, said she felt "disappointed by the numbers" on the night, adding: "I'm worried Hillary is not going to get the bounce she needs."

Eventually, a solution was found. The two giant television screens on either side of the room were switched off, throwing a veil – or a comfort blanket – of ignorance over proceedings in Lake County where it was still possible that Barack Obama had earned enough votes to beat her.

When Mrs Clinton took the stage she might as well have had her fingers crossed as she quoted her opponent's prediction last month that Indiana would be the tie-breaker. "Well, tonight we've come from behind, we’ve broken the tie," she said, "and thanks to you, it's full speed on to the White House." Her husband, Bill Clinton, stood behind her looking thoughtful with his hands clasped behind his back.

The surroundings were incongruously exotic for a presidential campaign which has chosen to pitch itself to the values of "six-pack Joes" and white working class America. The Murat Shrine Temple in Indianapolis, which was chosen as a venue for the rally last night, is a piece of architecture decorated with pharaohs and Islamic symbols that can best be described as "mock-Mosque".

But Mrs Clinton was not in the mood to demonstrate the "testicular fortitude" with which a union leader had admiringly said she was fighting this campaign. Instead, her speech was punctuated with moments of almost valedictory grace.

"I know that people are watching this race and they're wondering, I win, he wins, I win, he wins. It’s so close," she said. "I can assure you, as 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. It is time for all of us to recognise what is at stake in this election, not just for Democrats as we decide who will be our nominee, but for all Americans."

A campaign that has been living on thin air as it secured improbable last-ditch victories through Ohio, Texas and Pennsylvania, was last night falling back to earth. Mrs Clinton is running out of primaries to close Mr Obama's lengthening lead in delegates – and even her most dedicated supporters are beginning to suspect the end is near. A narrow victory in Indiana was not good enough.

Jesse Miller, a 21-year-old college student, said: "In my heart I really do believe she will be our next president. But in my head, I know that the math is against her."

Mrs Clinton later roused the crowd by declaring "it is so important that we count the votes of Florida and Michigan". Delegates from these two states are currently banned from the convention because they broke party rules by staging primaries in January.

But they both voted for her and an appeal to the rules committee on May 31 may yet be her best - last - chance of stopping Mr Obama winning the nomination.

"It would be a little strange to have a nominee chosen by 48 states," said Mrs Clinton, as her audience broke into a brief chant of "Count the votes! Count the votes!"

Mariam Rahmani lent over and whispered: "It's all a lot of bull**** but I still love her. She does what it takes and you have to admire that, don't you?"

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