With the 2008 presidential campaign in her rearview mirror, Senator Clinton is forging ahead: She has already begun preparations for her next run at political office, in 2012.

Mrs. Clinton’s campaign is reportedly sending letters to donors asking permission to transfer $2,300 worth of campaign contributions into her 2012 Senate election fund from the 2008 general election, rather than giving a refund.

The letter includes a note from Mrs. Clinton that says: “Dear friend, your commitment has meant so much to me over the course of my presidential campaign. You were there for me when I needed it the most and I’ll never forget it. I hope you’ll help me continue to fight for the issues and causes we believe in by filling out the enclosed form in support of Friends of Hillary.”

The form specifies that if a supporter has already donated to the 2012 primary election, they can also designate any amount in excess of $2,300 to Mrs. Clinton’s 2012 general election fund. If letter recipients do not respond by August 28, their contribution will be refunded automatically.

The New York Observer first reported the story on its Web site.

Last week, in an effort to unify the Democratic Party, Senator Obama appeared alongside Mrs. Clinton at a fund-raiser in New York and encouraged his supporters to help retire her more than $20 million campaign debt.

Some of Mr. Obama’s supporters have said it is outrageous to ask Democrats to repay Mrs. Clinton’s debt with the general election fast approaching. Mrs. Clinton made headlines by pouring millions of dollars of her own money into the campaign.