#1 He swore to uphold and defend the Constitution;
#2 He doesn't recognize the difference between the Constitution and the Declaration of Independence;
#3 He makes a comment about not caring about how the Constitution applies, however the statement could be defended when used in full context to show he was leaving that up to others to sort out or that the issues would be a vague stretch (not that I agree, but it is how I could see it playing out and him winning);
Based on #1 and #2 and avoiding bringing in #3 to muddy the waters, If I were from Illinois I would be bringing suit or petition concerning his not being aware of the oath he swore or the guidelines of his actions. Maybe recall would not happen, but I would hold him to #1 and #2 from now until the day he loses the next election! And, I would make sure it became an issue in everything put in front of him from now on.