While Mitt Romney is attempting to gin up enthusiasm among supporters for another run for the White House, one former donor is pouring cold water on the idea, encouraging other big money friends not to get behind the 2012 Republican presidential nominee.

“It isn’t just because we lost and just because our base didn’t show up,” conservative donor Randy Kendrick of Arizona said in an interview with The Daily Caller, discussing Romney’s defeat in the 2012 presidential election. “Those are pretty big reasons. But it’s because he couldn’t fight against the primary thing that motivates me and motivates millions of other Republicans: Obamacare.”

Kendrick — the wife of Arizona Diamondbacks team owner Ken Kendrick, and a frequent donor to conservative causes and candidates — has been emailing friends and other donors with arguments against supporting another Romney campaign.

“My family spent enormous time and money to elect Mitt Romney despite our concerns,” Kendrick said in the email, which has been sent to a variety of fellow donors, and was obtained by TheDC. “However, lesson learned, I will work early and tirelessly now to make sure he is not our nominee again.”

Kendrick, who as a result of her donations was invited to Romney’s Park City, Utah retreat for influential supporters in 2012, said she has not yet committed to another candidate for 2016 but likes Wisconsin Gov. Scott Walker and Florida Sen. Marco Rubio.

“Certainly, I would’ve preferred Romney over Obama,” Kendrick said by phone Tuesday. “But I now do not prefer Romney over any candidate that might be running.”

Kendrick referenced the criticism Romney often gets from conservatives that the health care plan he championed while governor of Massachusetts was later a model for President Obama’s health care law.

“He could never be a strong opponent of Obamacare for obvious reasons,” Kendrick said of Romney in the 2012 election. “And our entire base was opposed to this federal takeover, and yet he couldn’t fight against that.”

Kendrick also said she was disturbed to learn that former Utah Gov. Mike Leavitt, who Romney tapped to lead his transition team in 2012, ran a health care consulting firm that helped states implement Obamacare.

While Romney is busy wooing donors again ahead of a possible run, Kendrick said she isn’t specifically sure which donors are truly excited about a Romney re-run.

“I think people feel like we have an exciting group of accomplished and interesting Republicans,” Kendrick said of the emerging crop of candidates for 2016. “And we don’t need to repeat 2012.”

“I don’t know who the base is,” she said, “who the source of support for Romney is.”

After repeatedly saying he would not run again in 2016, Romney announced to donors in New York last Friday that he is considering a run again. Those who know Romney, who also ran in 2008, say he is serious about running for a third time and is likely to make a decision soon.

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