Prime Minister Lars Loekke Rasmussen, who heads the Liberals, has been in power since 2015. He later formed a coalition with the smaller Liberal-Alliance and the Conservatives. But it depends on the anti-immigration Danish People's Party and its 37 seats to muster a majority in the 179-seat parliament.
Overall, Danes have supported the government's tough stance on immigration after the 2015 migration crisis in which mostly Muslim asylum-seekers sought refuge in European countries, including Denmark.
Political experts say people who traditionally voted for the populists are drifting mainly to the Social Democrats, which have moved toward supporting a stricter immigration policy. Voters also appear to be turning away from the Danish People's Party because of fraud scandals involving European Parliament funds.
The government has notably adopted laws tightening asylum and immigration rules, including a ban on garments covering the face and a law requiring newly arrived asylum-seekers to hand over valuables such as jewelry and gold to help pay for their stays in the country.
Other laws include requiring anyone who becomes a citizen of Denmark to shake hands at the naturalization ceremony, a move widely seen as aimed at some Muslims who for religious reasons decline to touch members of the opposite sex. Another law sends rejected asylum-seekers or those with a criminal record awaiting expulsion to an island that once housed a defunct laboratory for contagious animal diseases.
Recent polls show Loekke Rasmussen's center-right government bloc trailing behind the five-party, center-left opposition headed by the Social Democrats. Surveys indicate the governing coalition will get 46% while the opposition would garner 54%.
In announcing the election, which comes just 10 days after the European Parliament vote, Loekke Rasmussen stressed that the government didn't resign. Under the Danish Constitution, a vote must be held by June 17, when the current parliament, elected in 2015, completes its term.
The election could mark the return to power of the Social Democrats, the country's largest party, which have spent four years in opposition.
In recent months, the Social Democrats have moved closer to the stricter immigration agenda of the Danish People's Party — a party with a euroskeptic line founded in 1995. The populists, now Denmark's second-largest party, grabbed more than 21% in the 2015 election in its best vote ever.
This time around, polls say the Danish People's Party will win 15% of the vote.