Yes! If you would like multiple rewards, you simply select the reward with the highest price, and then in the box where you enter your pledge amount, you add the dollar amount of the additional rewards.
For example: Say you want a $75 pair of Seekers, a $30 Patara Logo T-Shirt, and want a $5 Sticker. It's $75 + $30 + $5 = $110. Select the $75 reward option, and then type in $110. This applies to any combo of available rewards.