Diane James was in the Hampshire constituency for a rally with supporters aided by UKIP leader Nigel Farage.
Ms James, from Ewhurst in Surrey, said: ''Immigration is the elephant in the room that the other parties want not to address because they are heavily reliant on unrestricted immigration.''
When asked what she meant, Ms James said: ''Because in the last few years immigrants have settled in areas where there are a large number of Labour voters.
''On the 1st of January 2014 the floodgates will open for Bulgarian and Romanian citizens (to come to Britain),'' she continued.
''We are not just talking about pressure on services from immigration but also, and I have to say it, the crime associated with Romanians.
''One of the problems with the Olympics last year was the Metropolitan Police having to deal with Romanian criminal gangs pick-pocketing.''
She said that unrestricted immigration was an issue for the country.
''Until we sort out the UK Border Agency and make it fit for purpose, the only way is a moratorium on immigration.''
Ms James sits as an independent councillor on Waverley Borough Council in Surrey because she said she feels that party politics should not exist at that level.
She explained she wanted to make history by becoming the first ever UKIP MP and her election would send a very clear message to the three major parties about their broken promises.
She also said that not living in the constituency was not a problem.
''I know Eastleigh well. I used to work down here in the pharmaceutical industry, I have friends and family down here and I fly from the airport two or three times a year - it's an area I know.''
Mr Farage said his party was starting the campaign with 16% of the vote and that the figures showed the party was taking votes from Labour and the Liberal Democrats.
''One myth is that we just take votes from the Conservatives, we don't. We are going to fight this campaign hard,'' he said.
On immigration, Mr Farage said he had ''absolutely nothing'' against the 29 million people that will be able to leave Bulgaria and Romania next year but there should not be an open door policy for them.
He added that immigrants should only be given benefits if they have lived in Britain for five years, have paid their taxes and have obeyed the law.
UKIP are expecting to do well in the February 28 poll sparked by Lib Dem MP Chris Huhne standing down after pleading guilty to perverting the course of justice.
All the major parties have now selected their candidates except Labour who will do so today.
The contest is likely to be a close one between the Lib Dems and the Tories.
Mr Huhne held the seat in the 2010 general election with a majority of 3,864.
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