Former Rep. Ed Case is pointing to a leaked Democratic polling memo as proof that he is the only Democrat who can win the May 22 special election to succeed former Rep. Neil Abercrombie (D), who resigned to run for governor.

According to a memo accompanying a survey done by pollster Paul Harstad for the Democratic National Committee, Honolulu City Councilman Charles Djou (R) led the field with 36 percent, while Case had 34 percent and state Senate President Colleen Hanabusa had 20 percent.

The Democratic Congressional Campaign Committee paid for a robocall in which President Barack Obama asks voters to choose a Democrat but doesn’t specify which one.

“It’s crucial that you vote and that you vote Democratic,” Obama says in the recording. “In the next couple of days, an actual ballot will come directly to you in the mail and all you need to do is fill it in, sign the envelope and mail it back. Voting is that easy. I hope we can count on you to return your ballot as soon as you get it. Your vote matters. Thanks so much. Bye-bye.”

Ballots were sent out April 30 for the special election, which is being conducted entirely by mail.