Ms Mordaunt has taken an early lead in the most recent Conservative Home poll, after receiving 20 percent of the vote.
The MP for Portsmouth North released a campaign video on Sunday, appearing to make a dig at Boris Johnson, stating the party should not be about the individual leader.
Releasing her campaign, the international trade minister said the UK’s leadership “needs to become a little less about the leader and a lot more about the ship”.
The video featured a number of inspirational scenes from the world of sport, politics and of Britain.
Penny Mordaunt Aaron Chown
The video featured this scene of Oscar Pistorius Penny Mordaunt
But one scene in particular, of disgraced South African sprinter and convicted murderer Oscar Pistorius, led many to question Ms Mordaunt's judgment.
The Cabinet minister also included footage of athlete Jonnie Peacock in her video, who later requested the clip be removed.
Ms Mordaunt was Ben Wallace’s predecessor as Defence Secretary, and the first woman to hold the post before being sacked by Mr Johnson shortly after he became Prime Minister in 2019.
Ms Mordaunt has many strings to her bow as a Royal Navy reservist and former reality TV contestant, having appeared on the Tom Daley-fronted diving show Splash.
She played a prominent role in the Leave campaign in the 2016 Brexit referendum, and enjoys the backing of Dame Andrea Leadsom and Michael Fabricant.
MP for Saffron Walden, Kemi Badenoch, ascended to second place, receiving 19 percent of the vote.
In recent surveys by Conservative Home, Ms Mordaunt has remained a top favourite.
The current MPs running for the role of Conservative Leader are; Rishi Sunak, Sajid Javid, Penny Mordaunt, Liz Truss, Grant Shapps, Nadhim Zahawi, Tom Tugendhat, Suella Braverman, Jeremy Hunt, Kemi Badenoch, and Rehman Chishti.