According to German public television ARD, the chancellor received 96.7 percent of the vote, which is her second best result, following a record of 97.9 percent in 2012.
In addition to her election, the five deputy party leaders, including incumbent German Defense Minister Ursula von der Leyen, were re-elected at Tuesday`s conference.
During a speech ahead of the vote, Merkel called on her party to implement new reforms. She has been leading the conservative party since 2000. In her eight elections since then, the lowest backing she has ever received was 88.4 percent in 2004.
Merkel, 60, was elected to a third term as German chancellor in last year`s general elections. Her CDU and its Bavarian sister party Christian Social Union (CSU) formed a grand coalition government with the center-left Social Democratic Party (SPD) following the elections.
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