Former Minnesota Gov. Tim Pawlenty passed on criticizing former Massachusetts Gov. Mitt Romney’s healthcare plan on Thursday night, instead focusing on his own work in Minnesota.

Pawlenty said he did not see Romney’s Thursday afternoon speech defending his plan at the University of Michigan, but that he’d let Romney and voters make up their own minds about the controversial healthcare plan.

“I think Mitt Romney is the best person to address the Romney approach to healthcare. I can tell you the approach I took in Minnesota, and we took a different approach, and my vision for healthcare in the country is to make it more affordable – not by bringing it to government … but to empower consumers," he told Fox News.

Pawlenty’s refusal to criticize Romney’s healthcare plan is a relatively new development. In 2009, Pawlenty sharply criticized the plan in a series of media appearances, where he claimed the program led to the “most expensive healthcare in the country” and levied a “huge new tax structure.” He also used Massachusetts as a case point in a letter he sent to members of his congressional delegation, urging them to vote against Barack Obama’s health plan.

Yet in 2010, he dialed back explicit criticism of the healthcare plan, instead choosing to focus on his own work in Minnesota.

That strategy — according to sources close to the governor — reflects a desire to stay positive for as long as possible, while conservative pundits and think tanks do the heavy lifting of hammering Romney’s healthcare plan.