Washington ? President Bush on Saturday backed a resolution to amend the Constitution to define marriage as a union between a man and a woman even though the idea has little chance of being passed in the Senate.

“Ages of experience have taught us that the commitment of a husband and a wife to love and to serve one another promotes the welfare of children and the stability of society,” Bush said in his Saturday radio address. “Marriage cannot be cut off from its cultural, religious and natural roots without weakening this good influence on society.”

Democrats say Senate floor time is being wasted on the issue, and accuse Republicans of making a pre-midterm election appeal to social conservatives whose votes were key to Bush’s re-election.

This November, initiatives banning same-sex marriages are expected to be on the ballot in Idaho, South Carolina, South Dakota, Tennessee, Virginia and Wisconsin.

“Sadly, President Bush is playing election-year politics with this divisive issue,” the Rev. Barry W. Lynn, executive director of Americans United for Separation of Church and State, said Friday.

The White House said Bush did not devote his radio address to the issue or decide to host a presidential event Monday to again endorse the amendment because it is politically expedient, but because there’s a vote on it scheduled next week in the Senate.