Music legend Elton John has donated $20,000 to defeat a gay marriage ban due to be voted on in Wisconsin.

The gay artist has pledged his support as debate surrounding the issue mounts amid Congress elections and a vote on gay marriage next week.

His money will help gay campaign group Fair Wisconsin counter an anti-gay advertising campaign from the family Research Institute of Wisconsin.

Fair Wisconsin argues that a ban would also affect unmarried straight couples, The Washington Blade reports.

Supporters of same sex unions will be buoyed by last week’s decision by New Jersey’s Supreme Court which ruled that gays and lesbians should be given equal status before the law.

There will also be votes on the issue in Arizona, Colorado, Idaho, South Carolina, South Dakota, Tennessee and Virginia next week.

Sir Elton was one of the first British couples to take advantage of civil partnership laws when they were implemented in the UK last year.