During a conference call with top fundraisers Monday afternoon, Walker and his campaign manager were relatively candid in their assessment of the campaign’s shortcomings, according to notes of the conversation taken by a participant. Walker said the campaign will strive to do better in three areas: protest, passion and policy.

“We need to step it up and remind people that we didn’t just take on the unions and Democrats, we had to take on my own party establishment, those who did not want to take on the status quo,” Walker said on the call, according to the notes.

He added later: “One thing I heard about the first debate was: ‘You were fine, you did no wrong, but people want to feel the passion.’ ”

The steps mark a clear shift for a candidate who has long positioned himself as a potential bridge between the party’s conservative and establishment wings. Walker now intends to focus his energy primarily on challengers from the right — a constituency that is particularly important in the first-in-the-nation Iowa caucuses, which aides consider a must-win contest for him.