Today there was another important non-endorsement endorsement in the 2012 Republican primary. The Romney camp proudly sends around this report:

Sen. Pat Toomey of Pennsylvania, who has said he won’t endorse anyone in the Republican presidential race, on Friday praised front-runner Mitt Romney as a true conservative whom Republicans can trust as their nominee.

“I think Mitt Romney is a conservative, and I think if elected, he’ll govern as a conservative,” Toomey told reporters during a press conference at the Pennsylvania Leadership Conference, an annual gathering of conservative activists in the Keystone State.

Toomey’s remarks came during a week in which prominent Republicans have been urging their party to unite behind a presidential candidate. Former Florida Gov. Jeb Bush endorsed Romney on Wednesday. On Thursday, Sen. Jim DeMint of South Carolina — like Toomey — praised Romney without endorsing him.

The praise from DeMint and Toomey is significant because of their standing with parts of the GOP base. DeMint is a leading tea party figure, and Toomey is a former president of the antitax Club For Growth.

Interestingly, Toomey’s nod is in keeping with Right Turn’s “how to get rid of Santorum”guide (“a unified showing by the Pennsylvania congressional delegation and by Sen. Pat Toomey (R-Pa.) would give a powerful message”).

There is also a karma overload on this one. It was, of course, Rick Santorum’s backing of then-Sen. Arlen Specter (D/R/D-Pa.) in the 2004 Senate race over Toomey that helped Specter secure the win, gave President Obama the 60th vote on Obamacare and stained Santorum’s record as a principled conservative.

The non-endorsement endorsement raises the possibility that others in Pennsylvania will swing into the Romney camp, hampering Santorum’s ability to win in his home state. Would he insist on going forth with the primary on April 24, risking a humiliating loss?

As we know, even if he “won” the popular vote, Santorum would have another delegate fiasco on his hands. “In Pennsylvania, most delegates are elected on primary day. And each Republican delegate is free to support the candidate of his or her choice. So it’s important for presidential candidates to field a slate friendly to their ambitions.” This Santorum failed to do.

Pennsylvania may have more downside than up for Santorum. For a guy who can’t win the delegate race, why risk defeat in his home state? Besides, he has the perfect excuse not to go forward: He’s taking one for the team.

This is also a smart move by Toomey. Like DeMint, he gets credit for being a responsible party leader. It also reintroduces his name as a potential running mate. But mostly, it burnishes his own record as a staunch conservative who knows how to advance the ball for the right, which is sometimes incrementally.