Hundreds of people were rescued from Mediterranean boats or landed at the overcrowded entry point on the island of Lampedusa at the weekend, and five migrants were reported dead.
Although not especially unusual for the summer, the latest surge in crossings was leaped upon by the right-wing Brothers of Italy and League parties as they begin campaigning after Mario Draghi's unity government collapsed.
"On September 25, Italians can finally choose a change: security, courage and border control will be back," said Matteo Salvini, the hardline former interior minister and leader of the League.
Brothers of Italy, a party with neo-fascist roots, called for a "naval blockade" to stem the flow of people across the Mediterranean and clamp down on illegal migration.
Sea arrivals in Italy are up by 33 per cent compared with last year, according to the UN's refugee agency UNHCR.
The majority of those arriving came from Libya or Tunisia, although some are taking a longer route via Turkey that was first observed last year. Bangladeshis, Egyptians, Tunisians and Afghans have made up the majority of this year's arrivals.
The reception centre at Lampedusa is currently housing 1,871 people when it is only designed for 350, news agency Ansa reported, while rescuers said they had picked up hundreds more migrants in the Mediterranean.
Ms Meloni is seen as a front-runner to be the next prime minister, with Brothers of Italy holding a narrow lead in the polls - having sidestepped the recent political turbulence by never being part of Mr Draghi's coalition.
A right-wing government could bring Ms Meloni's party into coalition with Mr Salvini, who drew notoriety for clamping down on migrant boats in his 18 months as interior minister.
Mr Draghi's stated approach was to work with Libya and Tunisia, to try to address the root causes of migration in sub-Saharan Africa, and to put pressure European neighbours to take a bigger share of the migrants.
He resigned when most MPs failed to back his unity government in a confidence vote, after manoeuvres by Mr Salvini, former prime minister Silvio Berlusconi and others to bring him down.