The NPP filed a petition over the election result at the Supreme Court in late December, saying it had found irregularities including unregistered voters casting ballots.
Liberal Democrat leader Nick Clegg has led moves for a "recall" mechanism that would be triggered if 5% of constituents signed a petition demanding a by-election.
The drive to recall Mr Walker picked up steam last November after unions defeated similar measures at a referendum in Ohio, and since then over 900, 000 Wisconsinites have signed the petition demanding Mr Walker face a fresh election, almost twice the number needed.
Two groups seeking to stop Mahony's participation in the election said Saturday they have collected nearly 10, 000 signatures on a petition against his involvement.
The court said it would rule Thursday on another petition from a man whose candidacy for the Oct. 6 presidential election was rejected by the election commission.
Four of the suspended appeal court judges ruled against a petition Mr Kibaki filed when he was an opposition leader, challenging Mr Moi's election victory in 1997.
"We are ready to concede that in an election that involves more than 11 million voters there might be mistakes, " said Mr Akufo-Addo after the petition was filed at Supreme Court in Accra.