0105 GMT February 20, 2019
Following a two-round vote cast by 999 delegates at a party congress in the German city of Hamburg on Friday, Karrenbauer, 56, ultimately won 517 votes, defeating millionaire corporate lawyer Friedrich Merz, 63, who gained 482 favorable ballots.
Merz had also sought to lead the party in 2002, but was ultimately defeated by Merkel. Considering Karrenbauer as Merkel's protege, many CDU members who were tired of Merkel's consensual politics, voted for Merz in the latest round of elections.
Third candidate and current Health Minister Jens Spahn was eliminated in the first round of voting, Presstv reported.
The run-off vote between Kramp-Karrenbauer and Merz was preceded by a final speech by Merkel.
The German chancellor described a "balanced budget policy", the "management of the refugee crisis" and the end of military conscription in 2011 as major party achievements during her tenure.
The long-time party leader received a 10-minute long standing ovation after finishing her speech.
Merkel, who has been Germany's Chancellor since 2005, announced her surprise resignation from political life on October 29, giving up leadership of the conservative party, yet vowing to finish out her full term as German chancellor until 2021.
The announcement came only one day after the CDU and the allied Social Democratic Party (SPD) suffered heavy losses in the Hesse state election.
Speaking earlier after a similarly weak performance in the Bavarian elections, Merkel admitted that German voters had lost trust in their government.
The German chancellor took "full responsibility" for the poor performance, ultimately deciding to resign.
Karrenbauer, former CDU secretary general and Saarland state premier, was known to be Merkel's presumed favored successor.
Presenting herself before the final vote on Friday, Karrenbauer pointed out that she is known to be a "mini Merkel," however, adding that "I can tell you that I stand here as my own person, just as life has shaped me and of that I am proud."
Karrenbauer, described as a Merkel-loyalist, gained the nickname out of her pragmatic and centrist politics which shadow that of Merkel.
The politician has also been described as having a reputation for uniting factions across the CDU along with other parties.
Facing tough competition from the emerging and right-wing Alternative for Germany (AfD) opposition party, Karrenbauer seeks to maintain the CDU’s position as Germany’s catch-all party.
The party's former secretary general is, however, known to support some social and foreign policies opposed by even her veteran predecessor Merkel.
Unlike Merkel, Karrenbauer is a supporter of special women quotas on corporate boards and adopting a tougher line against Russia.