BERLIN, Nov. 15 (Xinhua) -- The race to succeed German Chancellor Angela Merkel as Christian Democratic Union (CDU) leader is entering its decisive phase on Thursday as candidates convene for the first of eight regional party conferences which will culminate in a vote by the national party convention on Dec. 7 and 8 in Hamburg.

The hosting governor of the first party conference, Daniel Guenther, told the German press agency (DPA) that he expected the "entire range of current topics" to be addressed while refusing to endorse any candidate at this point.

Following the last regional elections in Germany, Merkel announced not to run for CDU leader again in December and to leave German politics entirely after her fourth term as chancellor.

Although a large number of less prominent party members have also thrown their hats into the ring, CDU secretary general Annegret Kramp-Karrenbauer, health minister Jens Spahn, and former CDU faction leader Friedrich Merz are widely regarded as the three most promising candidates.

Merz, who worked as acting chairman of BlackRock, most recently described the regional conference as an opportunity to get to know the candidates in close proximity and announced that he would explain how he imagined "reform and renewal in the party." Similarly, Spahn told press on Thursday that he stood for a "new start, a change of generations" in the CDU.

Spahn and Merz both stand for conservative values and have repeatedly criticized the German immigration policy under Merkel. By contrast, Kramp-Karrenbauer is generally considered to be a close ally of the chancellor and a supporter of Merkel's ideologically pragmatic course.