Well, according to ESPN's Chris Mortensen Manning had a workout for Jim Harbaugh and the 49ers this week, and even took a physical for them, effectively joining the race late. But late is always better than never:
Filed to ESPN: Third team in Manning race that has emerged is49ers - Manning worked out for Harbaugh &took physical this week #NFL32— Chris Mortensen (@mortreport) March 16, 2012
This would clear up some of the confusion of Alex Smith's contract status as well, as the team has basically put signing Smith on the back burner (or off the heat completely) while quietly making a play on No. 18. From his other suitors in Tennessee and Denver, the 49ers would be leaps and bounds the most talented team he could join, and with all the cap space they've been opening up, the numbers could line up just right to land him.
For more on the possibility of Manning as a 49er, head over to Niners Nation to get in on the action.