[Austin Willard Wright]

I thought Barbara Lee was the only dissenter

You're thinking of an early resolution (in late 2001), which essentially authorized the Afghan War (which Paul supported). The second resolution from 2002on Iraq had a number of dissenters, mostly Democrats but a few Republicans (including Paul).

[Revenge of Sith]

However, it's inconsistent of Paul's defenders hide behind the "Congress should declare war" spin to justify his vote against the war in Iraq since he did vote to authorize military force in Afghanistan without a declaration of war.