Bayern's path looks a bit easier in common, but Leipzig will be a tough nut to crack plus Schalke which are desperate to leave the relegation zone could prove to be a problem. I'm rather optimistic about Dortmund's chances - I don't believe they will take all 15 points, but I don't believe Bayern will take their 15 points.
I think the paths are quite even for both. If Dortmund isn't totally insane, they are going to win that away game against Bochum first. Bayern vs. Hertha is a win for Bayern.
At home Dortmund has been the strongest team this season with 12 wins, 1 draw and 1 loss. I don't think with this motivation they are going to lose a single point at home. The only game that my actually threaten them is Augsburg.
Bremen shouldn't be underestimated, but is probably a win for Bayern. But they still have Leipzig and I am very sure that Leipzig will also be fighting for the champions league qualification. Bayern won 9 out of 14 games at home. I think there is a chance for Leipzig to tie the game.
Union Berlin made the punch today and took those 3 points home. One of the most important 3-pointer of the season for them in my opinion as they now have 4 points over Leipzig. This might have been the qualifier for them.
If you look at the standings of the teams, then Bayern's path is a little, but easier - because they play literally with the two worst teams in the Bundesliga. Mainz is easier for Dortmund than Leipzig is for Bayern, but this is probably the only pair of the 5 remaining where Bayern are in a slightly worse position - the rest are either equal or in favor of Bayern. In any case, bookmakers consider Bayern as the clear favorite: