Retiring Sen. Joe Lieberman (Conn.) today declined to endorse a candidate to be his successor, leaving open the possibility he would back a Republican to replace him.

Lieberman, who left the Democratic Party to become an Independent after losing a 2006 primary, confirmed at a breakfast hosted by the Christian Science Monitor that he has met with the GOP hopefuls in the race. He said he was waiting for the primary process to play out and said that it was “possible” he would back a Democratic Senate candidate.

Lieberman met earlier this year with Republican candidates former World Wrestling Entertainment CEO Linda McMahon and former Rep. Christopher Shays.

The Senator told reporters today that he and McMahon discussed foreign policy but said she did not ask for his endorsement.

He described Shays as an “old, dear friend.”

“We’re keeping in touch,” Lieberman said.

Lieberman said that “conventional political wisdom” would indicate that McMahon’s “resources are so great, she would have an advantage, but this is an unconventional year.”

As for the presidential campaign, Lieberman might not get involved at all this time around. He drew ire from Democrats four years ago by endorsing and actively campaigning for Sen. John McCain (R-Ariz.) He also spoke at the Republican National Convention and helped vice presidential nominee Sarah Palin prepare for her debate against Joseph Biden.

“I’m enjoying not being involved in elective politics,” Lieberman said. “It’s possible I won’t endorse anybody. But if I do, I’ll do it as the Independent I was elected for this last term.”