Merkel, who has been chancellor since 2005, announced in late 2018 that she wouldn't seek a fifth term. She also stepped down from the CDU leadership.
The decision ends an 11-month leadership limbo in Germany's strongest party after outgoing leader Annegret Kramp-Karrenbauer, who had failed to impose her authority on the party, announced her resignation. A vote on her successor was delayed twice because of the coronavirus pandemic.
There had been no clear favorite going into Saturday's convention, but the election of Merz would have marked at least a symbolic break with the Merkel era. Laschet will now have to work to strengthen party unity something Kramp-Karrenbauer struggled with.
Laschet, 59, was elected in 2017 as governor of North Rhine-Westphalia state, a traditionally center-left stronghold. He governs the region in a coalition with the pro-business Free Democrats, the CDU's traditional ally on the right, but would likely be able to work smoothly with a more liberal partner, too.
Laschet pointed Saturday to the value of continuity and moderation.
We must speak clearly but not polarize, he told delegates. We must be able to integrate, hold society together."
He said that we will only win if we remain strong in the middle of society.
Laschet said that there are many people who find Angela Merkel good and only after that the CDU. He added that we need this trust now as a party" and that we must work for this trust.
Saturday's result will now be officially endorsed in a postal ballot which is expected to be a formality but is required by German law.
The CDU is part of the Union bloc along with the Bavaria-only Christian Social Union, and the two parties will decide together on the center-right candidate for chancellor. The Union currently has a healthy poll lead, helped by positive reviews of Merkel's handling of the pandemic.
CSU leader Markus Soeder, the governor of Bavaria, is widely considered a potential candidate after gaining in political stature during the pandemic. Some also consider Health Minister Jens Spahn, who supported Laschet and was running to be his deputy, a possible contender.
Business Standard has always strived hard to provide up-to-date information and commentary on developments that are of interest to you and have wider political and economic implications for the country and the world. Your encouragement and constant feedback on how to improve our offering have only made our resolve and commitment to these ideals stronger. Even during these difficult times arising out of Covid-19, we continue to remain committed to keeping you informed and updated with credible news, authoritative views and incisive commentary on topical issues of relevance.
We, however, have a request.
As we battle the economic impact of the pandemic, we need your support even more, so that we can continue to offer you more quality content. Our subscription model has seen an encouraging response from many of you, who have subscribed to our online content. More subscription to our online content can only help us achieve the goals of offering you even better and more relevant content. We believe in free, fair and credible journalism. Your support through more subscriptions can help us practise the journalism to which we are committed.
Support quality journalism and subscribe to Business Standard.