Try looking for "landing gap" in the TEXT area of the properties dialogue box if you've already created your leader/text (multileader). Or in your multi-leader style under the CONTENT tab.
If you are in dimension style, look under the TEXT tab for "offset from dim line"
Or try typing DIMGAP
Hope one of these gets whatyou need.
Windows 7 Prof. x64
HP Z400 Workstation
Intel(R) Xenon(R) CPU
W3550 @ 3.07GHz
6.00 GB RAM