I would be concerned that adding a vote button to each node would:

• Encourage/facilitate hasty (and possibly ill-considered?) voting.
• Add to the load on the server (admittedly, without any specific knowledge of their current loading).
• Require some distinctly non-trivial patching to effect.

To ease the tedium, you could open, in a new tab, any node upon which you wish to vote, singleton... if you would find that less burdensome.