President Obama warned supporters that this year could be the last time he celebrates a birthday as president because, he says, he’s “being significantly outraised” by Mitt Romney.

“My upcoming birthday next week could be the last one I celebrate as President of the United States, but that’s not up to me — it’s up to you,” Obama said in the email. “This July deadline is our most urgent yet, coming after two consecutive months of being significantly outraised by Romney and the Republicans.

Obama told donors that a $3 contribution would cause them to be entered into a raffle to attend his birthday party next week.