Desperate Barack Obama supporters are offering to trade everything from math tutoring to massage therapy for a ticket to the Democratic presidential hopeful`s sold-out victory rally in Chicago Tuesday.

The Obama campaign has done its best to prevent sales of the free tickets by requiring supporters who managed to sign up for the 65,000 passes to show photo identification.

But there is no name attached to the `plus one` part of the ticket which allows ticket-holders to bring a friend, and scores of people are capitalizing on their luck.

Sam Cooper offered his extra ticket on the online website Craigslist to anyone willing to hand over the keys to `an old running car for my son.`

`I have a teenage son who`ll need a car soon, as long as the car you have is in running condition and is not a complete clunker, we can do business,` the ad said.

Reached by AFP on Monday evening, Cooper said he has had a number of interesting offers -- including `very polite offers of sex` which he had no interest in -- but hasn`t decided who to give the ticket to yet.

He also posted an ad offering the ticket to a `Bible-thumping Christian` and said in an email, `I have `faith` in some more crazy answers about their religion.`

Some people are using their tickets to try to find love, or even a job while others are simply looking for cold, hard cash.

One person with two passes to the rally in Chicago`s downtown Grant Park offered to sell the two `plus one` spots for 1,000 dollars.

`No sob stories need apply -- we`re saving to put 3 kids through college, so I don`t need to hear about your student loans and how you can only afford 20 dollars,` the ad said.

The big prices have offended a number of people, whose angry rebukes can be found scattered through the more than 600 posts linked to Obama.

One person gave their location as `Leftout` and wrote, `This is seriously distgusting (sic) Especially where there are volunteers like myself and others who can`t even get it.`

About a million people who were unable to get tickets to the rally are expected to make their way to the sprawling lakefront park on Tuesday night. City officials have promised to try to accommodate them.