The leftist USL, backed by parliament, suspended Basescu earlier this month, saying he had overstepped his powers. European Union leaders have criticised Ponta for his campaign to oust his political rival.
Sixty-six per cent of the 1,104 people polled said they wanted Basescu to be impeached, with 34 per cent against. The president is unpopular for backing austerity measures, including salary cuts and a rise in sales tax.
Sixty-one per cent said they would vote in the referendum, the survey by pollster CURS for local newspaper Jurnalul National found.
Romania’s Constitutional Court has ruled that more than half the electorate must turn out for the referendum to be valid, a decision which improved Basescu’s chances of surviving.
Voter support for the USL has risen to 63 per cent, according to the poll conducted on July 11-16, despite the international criticism Ponta has received this month.
That indicates Ponta is likely to stay in power in the election due in November. A March opinion poll had put support for the USL at 48.4 per cent.
The political turmoil and policy paralysis caused by the dispute between Ponta and Basescu have raised concerns over a 5 billion euro ($6.11 billion) International Monetary Fund-led aid deal.
Markets have also been rattled, sending the Romanian leu to all-time lows against the euro.