BERLIN, Dec 2 (Reuters) - RB Leipzig struck twice in the first half to edge past visitors Heidenheim 2-1 on Saturday and leapfrog Borussia Dortmund into fourth place in the Bundesliga.

The hosts took a 29th-minute lead through a well-struck Lois Openda penalty and doubled it a minute before the break when David Raum charged down the left and crossed for Yusuf Poulsen to tap in.

Heidenheim cut the deficit in first-half stoppage time, however, when Benedikt Gimber slid in at the far post to stab home from a corner with the Leipzig defence caught napping.

In a dominant second half, the hosts should have scored more goals.

They missed several golden chances, including two late one-on-ones for Openda against Heidenheim keeper Kevin Mueller and twice hit the woodwork.

Leipzig moved to 26 points, two ahead of fifth-placed Dortmund, who take play leaders Bayer Leverkusen on Sunday.

Second-placed Bayern Munich, on 32, will not be in action this weekend after heavy snowfall in the Bavarian capital forced the postponement of Sunday's match against Union Berlin. (Reporting by Karolos Grohmann, editing by Ed Osmond)