Activist group GetUp has given federal MP Nick Xenophon a taste of his own political stunts, bringing two donkeys to a rally as it accused him of selling out taxpayers by striking a deal with the Federal Government to pass company tax cuts.

Senator Xenophon has developed a reputation over the years for using media-enticing stunts to make political points on a range of issues.

GetUp members rallied in Adelaide today, with two donkeys in tow, and delivered a petition to the Senator's office.

The organisation's national director Paul Oosting said pressure would be stepped up on the senator, who planned to field candidates for next year's South Australian election.

"Nick Xenophon had once said the trouble with horse trading is that you might end up with a donkey or you might make an ass of yourself. Well, in this case he's done both," he said.

Senator Xenophon called the GetUp protest "bizarre" and said he had worked well with the organisation in the past.

"I know that GetUp had a couple of donkeys at their rally this morning — I suggest that the people who have made an ass of themselves are GetUp," he said.

The NXT senator defended his backing of the Government's tax deal.

But a plan to give welfare recipients a one-off payment to help them meet their bills failed to impress protesters, with one at the rally commenting that it was a "lollipop in exchange for the future of my children".

In exchange for Senator Xenophon's support, the Federal Government has promised to look into ways to reduce energy prices and enhance power security.

Bizarre Xenophon stunts attract media attention

Nick Xenophon has used his own bizarre stunts to gain political attention and media coverage over his years in state politics and then in the federal arena.

The MP used a donkey as he claimed political horse trading could leave voters with a donkey, or worse still making an ass of themselves. ( Supplied: The Monthly )

A long-time campaigner against the adverse social impact of poker machine gambling, he made his point by smashing up a poker machine in a wrecker's yard.

When the Greens ran television advertising targeting the senator, he responded by bringing a pig to a media conference and saying election campaigning should involve "no porkies". (Get it?)

There was also the time the South Australian senator confronted then-defence minister David Johnston in Adelaide to demand the Government announce what share SA could expect of a deal to build more naval submarines.

His stunt? Enlisting an Elvis impersonator to croon Where's The Tender? to the tune of Love Me Tender.

Nick Xenophon and the Elvis impersonator. ( Twitter: Nick Xenophon )

Before the last federal election, campaign posters started appearing on street poles before Malcolm Turnbull had made the formal announcement of when polling day would be, so the senator took aim at that contravention of electoral laws.

The next SA election is just five months away. ( Twitter: Nick Xenophon )

When citrus was rotting on trees in the Riverland while a local juice company was packaging imported concentrate, the senator, with state MP Tim Whetstone, made his point by pouring juice down a drain in a busy city street.

Nick Xenophon and Riverland MP Tim Whetstone were upset a local firm was using foreign juice. ( Twitter: Nick Xenophon )

There has also been a toy train he brought to a media conference to make his point about MPs being on a "gravy train"; there was a "cash" cow he brought along to make another political point; and the MP once took to Adelaide streets wearing a huge sandwich board to thank voters after his strong showing on election day.