A MIRFIELD town councillor has defected to the far-Right British National Party.
Roger Roberts, a Conservative for 45 years, is leaving the party for the BNP.
Kirklees BNP councillor David Exley said the defection was a breakthrough for the party in Mirfield.
He added: "Roger came to us several months ago and expressed his admiration for the party and our policies.
"At first we kept him at arms length, because we were not entirely sure what he wanted. But soon it became clear he was genuine," said Clr Exley, a Heckmondwike representative.
"About a month ago he came to one of our meetings and said he was leaving the Conservatives and wanted to join the BNP. We are very pleased with his decision, because it means there is a BNP member on Mirfield Town Council.
"With the by-election next week it could be two soon."
Karl Hanson hopes to win a second BNP seat on the council when voters go to the polls next Thursday.
But the Mayor of Mirfield, Tory councillor Martyn Bolt, was not worried by the BNP in the town.
He said: "Roger has always been to the Right of the party. He has not been very active in it recently.
"I do not see this as a great loss for us or the people of Mirfield.
"It does mean there will be a BNP representative on the town council, but I don't think it will make any difference, because he will be so massively outnumbered."
Mr Roberts was expected to give more details about his decision later today.
The chairman of Mirfield Conservatives, Colin Fretwell, has called for him to resign.
He said: "We will be asking him to do the proper thing and stand down. The people of Mirfield did not vote BNP, yet they have a BNP town councillor."
The by-election was called after Conservative Lester Edon failed to attend the required number of meetings.
The candidates are: Roy Dobson (Labour), Michelle Gilbert (Conservative), Karl Hanson (BNP) and Imelda Marsden (Independent).