Here are penpix of the two men: DONALD TUSK Kingpin of the Civic Platform movement, Tusk, 54, aims to make history by becoming the first incumbent prime minister to win a second mandate since the demise of Poland's communist regime in 1989. He cruised into office in a 2007 snap election after Kaczynski's fractious coalition government collapsed. Civic Platform has held all the levers of power since July 2010, when its candidate Bronislaw Komorowski beat Kaczynski in a presidential poll caused by the death of his twin and head of state Lech Kaczynski in a plane crash in Russia. In 2005, Tusk was pipped for the presidency by Lech Kaczynski just weeks after losing a general election to the twins' Law and Justice party. Since bouncing back in 2007, Tusk has worked to repair Kaczysnki-era rifts with European Union allies. He has taken a firm line on Poland's national interests, however, questioning eurozone bailouts and declining to set an adoption target for the euro currency. His mandate has been capped by Warsaw's six-month presidency of the 27-nation EU. Tusk, a confirmed economic liberal since his youth, is proud of a stewardship which saw Poland as the only EU nation to keep growing during the global crisis. An underground journalist during communist rule, when he studied history, Tusk also ran a painting firm -- small companies were rare, but allowed by the regime. After 1989, he and a group of friends in his Baltic Sea hometown of Gdansk founded the Liberal Democratic Congress to push for sweeping privatisation of the state-run economy. In 1991's elections, it won 37 seats in Poland's 460-seat lower house. After losing them two years later, it merged with the larger Freedom Union. Tusk led a breakaway in 2001 and formed the Civic Platform. In line with his economic thinking, he admires of the late US president Ronald Reagan and former British premier Margaret Thatcher. He has also been a faithful supporter of Lech Walesa, the former Gdansk shipyard electrician who led the communist-era opposition trade union Solidarity and was elected president in 1990. Tusk is a proud Kashubian -- a Slav minority. He discovered his roots as an adult, prompting him to learn the language and write a teach-yourself textbook. A keen footballer, he is married to historian Malgorzata and has two adult children, one of whom is a well-known fashion blogger. JAROSLAW KACZYSNKI Left reeling by the April 2010 disaster in Russia that killed his identical twin Lech Kaczynski and 95 others, including first lady Maria Kaczynska and dozens of close political allies, Jaroslaw Kaczynski returned to the political fray within weeks. The 62-year-old conservative now hopes to steer his Law and Justice party back to power, and has tempered much of his hardball rhetoric. Jaroslaw, the elder twin by 45 minutes, and Lech were child stars, appearing together in a 1962 Polish film titled "The Two Who Stole The Moon" about a pair of scheming youngsters. They went to the same Warsaw high school, and both earned law doctorates. As activists in the communist-era Solidarity opposition, they were close to its charismatic leader Walesa, and helped to push the regime bloodlessly from power in 1989. But they fell out with Walesa after he became post-war Poland's first democratic president in 1990. After a decade in the political wilderness, Jaroslaw rebounded when the twins created Law and Justice in 2001 to unite a fractious right-wing scene. Lech became mayor of the capital, Warsaw, in 2002. Law and Justice's election campaigns of 2005 were masterminded by Jaroslaw. The two found themselves all-powerful after Jaroslaw became prime minister in July 2006 after a government shake=up. Their double act exasperated other EU leaders, and was equally controversial at home. While their conservative, nationalist vision rallied a swathe of society in deeply Catholic Poland, notably in small towns and the countryside, it alienated many urban and younger voters. Jaroslaw's coalition with a far-right party and a populist movement finally unravelled in 2007 and he lost a snap election to Tusk. Jaroslaw Kaczynski is unmarried and lives with his ailing mother.