Eleven Republican candidates will face off tonight in the main debate on CNN, and four more who didn’t qualify for the prime-time event will be featured in the early “undercard” debate. There’s no shortage of advice for the candidates, suggestions on what to look for, or assessments of what they need to do to win.

Politico suggests that the candidate with the biggest stake in tonight’s debate is Wisconsin Gov. Scott Walker:

Scott Walker’s last best chance

Scott Walker needs to reassure his …