Conservative MP Christopher Gill announced his defection to UKIP yesterday, as he urged fellow Eurosceptics to "come out of the closet" and join him.
Christopher Gill, who represented Ludlow in Shropshire for 14 years, said many Tory MPs secretly shared his belief that Britain would benefit from leaving the European Union.
He said he was turning his back on former allegiances in protest at Conservative leader David Cameron's criticism of the anti-European party as "closet racists".
Mr Gill also attacked Mr Cameron's decision to give roles to "dinosaurs" such as Lord Heseltine and Charles Clarke, who are on the pro-European wing of the party.
"I know from my experience in Parliament, and my contact with people in Parliament today, that there are quite a number of Conservative members, and probably MPs in other parties too, who secretly agree with what UKIP is trying to do.
"It is just sad they won't have the courage to do what is right for our country and come out of the closet and say so."
His decision to leave the Conservatives followed Mr Cameron's now-infamous radio interview in which he claimed that "UKIP is sort of a bunch of fruit cakes and loonies and closet racists mostly".
Mr Gill said: "If that is how the hierarchy of the Conservative Party really think then my decision to abandon any hope they are going to lead us out of the European Union is correct, and the future lies in UKIP."
Membership of the EU costs Britain #12 billion a year or #1.3 million an hour, he said.
"There are also costs affecting all of our businesses, such as the plethora of regulations and the risk that we become increasingly uncompetitive in world markets."
Mr Gill, who is 70 this year, said he would not stand as a candidate but he hoped other politicians would join UKIP.
"UKIP will I hope, and I hope what I have done will encourage people to do this, pick up more support and get more prominent people to join them.
"I hope they will go from strength to strength, because they have a message a huge number of people in this country want to hear."
He added: "I am very concerned about the direction in which the party is heading on the European issue, which is very fundamental and important to the future of our nation."
He had given up hope that the Conservative Party could be bought round to the view that Britain should leave the EU, he said.
"The three main parties are avoiding any discussion of these topics but when you scratch the surface and talk to the proverbial man in the street, he is very concerned that we have lost control of our own laws and government."