Premier Lars Loekke Rasmussen's ruling coalition, under the influence of its parliamentary partner, the anti-immigration Danish People's Party (DPP), has toughened immigration and border control in recent years.
The coalition of Rasmussen's Liberal Party and its Conservative Party junior partner has been in power since 2001, and enjoys parliamentary backing from the DPP which won nearly 14 percent of the vote in 2007 elections.
The coalition has presided over the development of one of Europe's most restrictive immigration policies and recently reintroduced permanent customs controls at its borders in a move criticised within the EU.
But such policies could soon be a thing of the past, with recent polls handing a comfortable lead to the centre-left opposition, which has vowed to loosen immigration restrictions and rescind the new customs initiative.
Ending weeks of speculation on an election date, Rasmussen told journalists on Friday: "I have advised her Majesty the Queen that general elections will be held on Thursday, 15 September. I wish all Danes a good election."
The prime minister, appointed two years ago to replace Anders Fogh Rasmussen when he was named NATO's secretary general, was required to call elections before 12 November.
A Megafon survey published by the Politiken daily on Friday put the opposition in the lead, with 52.2 percent of more than 1,000 people questioned this week saying they would vote for the centre-left parties.
This would translate to 90 seats in the 179-seat parliament.
The government and its far-right ally, meanwhile, garnered only 47.8 percent of support in the poll, or 85 seats.
A Voxmeter poll conducted last week for the Ritzau news agency handed an even clearer lead to the opposition, which it showed garnering 96 parliamentary seats compared to 79 for the current government and its DPP ally.
That spells bad news for Rasmussen, who risks losing his spot as Liberal Party leader if he fails to secure victory in his first vote at the helm.
Helle Thorning-Schmidt, the head of the main opposition Social Democrats who could become Denmark's first woman premier, said Friday she was gearing up for victory.
"After 10 years with Lars Loekke (Rasmussen) and (DPP leader) Pia Kjaersgaard, Denmark has ground to a halt," she told reporters, stressing that "I and all Social Democrats are looking forward to making a difference for Denmark."
Rasmussen, however, insisted his government was best placed to guide the Scandinavian country through the effects of a swelling global financial crisis.
Denmark's economy, he said, needed more of the current government's "responsible economic policies ... not irresponsible wishful thinking."
On Wednesday, the government presented a bleak 2012 budget proposal, forecasting a ballooning deficit next year of nearly 85 billion kroner (11.4 billion euros, $16.5 billion), or 4.6 percent of gross domestic product, and slowing growth this year.
It remains unclear if the draft budget will ever be debated in parliament, which does not reconvene until early October, since the balance of the house will likely shift after the upcoming vote.
Political analysts say Rasmussen's government is heading for the polls in a weakened position, especially after it failed to gain backing from the DPP for its high-profile economic stimulus initiative, presented Tuesday.