Workers' Party (WP) chairman Sylvia Lim said the People's Action Party should be "gentlemanly enough to tell the facts" about the financial situation of Punggol East.
And if it did not have a good answer, it would be the ruling party that is "finished", and not the opposition party, she added.
"Today is the last day of campaigning, Sept 9. There are just 21/2 hours more before Cooling-off Day starts," said Ms Lim at a WP rally last night. "We are still waiting for the PAP to come back on the definitive clarification."
The WP has come under fire from the ruling party for lapses in the opposition party's Aljunied- Hougang-Punggol East Town Council (AHPETC).
Last Saturday, WP chief Low Thia Khiang held up a page of Punggol East's accounts at a WP rally to show it had an operating fund account deficit of $282,009 when the WP took over in 2013. This did not square with what PAP Punggol East candidate Charles Chong had told Chinese papers that there was a $1 million surplus, he said.
Yesterday, Ms Lim said various PAP leaders had not explained this issue sufficiently. She said some of them had accused Mr Low of not presenting the full picture with only one page of the accounts.
PAP organising secretary Ng Eng Hen said on Sunday the party would put the facts on record. "If Mr Low agrees with the facts, he may have to issue a correction. I hope he's gentlemanly enough to accept that he was wrong in this regard."
Ms Lim pointed out that Pasir Ris-Punggol GRC candidate Zainal Sapari had released another page of accounts to show Punggol East had a surplus of about $21,000.
She said her party had put online all 25 pages of the accounts on Tuesday. "Can they tell us which page out of the 25 pages we should look at? Where can we find the $1 million surplus that Charles Chong spoke about?" she asked.
Ms Lim also asked if the PAP was trying to "mislead the public and damage AHPETC".
Last night, Mr Chong issued a statement saying he had been "deliberately misquoted" by WP. He said he was referring to the Pasir Ris-Punggol Town Council having a surplus in excess of $1 million in the newspaper report, and not Punggol East constituency.
Responding last night, WP Hougang candidate Png Eng Huat said his party did not misquote him. "The facts are clearly contrary to the statements made by the PAP. We hope the PAP will issue a correction to their misleading statements."
Mr Png also hit back at Mr Chong for a "baseless allegation" over sinking funds transferred to AHPETC. Mr Chong had said in a flier that $22.5 million from Punggol East's accounts, transferred to AHPETC's sinking fund after the 2013 by-election, was now unaccounted for.
To this, Mr Png said: "The statement is incorrect and a malicious attempt at discrediting the WP. The sinking fund transferred from Punggol East to AHPETC is clearly accounted for."