My understanding is that some of the Scandinavian synods (like the Finnish and Swedish) have apostolic succession. Most of the North American synods do not track it.
I do not know the exact lineage of the Swedish Lutheran episcopacy, but it is sufficiently within the apostolic succession to have retired (in my opinion, apostate) Bishop Kristen Stendahl serve as one of the co-consecrators of the infamous (and, again in my opinion, equally apostate) Episcopal Bishop of New Hampshire, Vicky Gene Robinson.
The 1999 Evangelical Lutheran Church in America (ELCA)-Episcopal Church agreement "Called to Common Mission" (CCM) spells out a procedure for bringing all future ELCA Bishops into the apostolic succession through requiring at least 3 Bishops (either Lutheran or Episcopal) who are within the succession taking part in the elevation of new Bishops.
CCM has provoked a major backlash, particularly in the upper Midwest among congregations whose roots extend into the former American Lutheran Church. The Word Alone movement and its spinoffs all began in response to CCM. Too much to go into on a thread originally about the Nativity movie! This