Lieberman doesn't rule out GOP run

WASHINGTON, Dec. 16 (UPI) -- U.S. Sen. Joe Lieberman, Ind-Conn., a former Democrat, says he hasn't ruled out running as a Republican in 2012.

Lieberman, whose transformation from a one-time Democratic U.S. vice presidential nominee to a right-leaning independent earned him many critics in his former party, told CNN Tuesday he hasn't decided what, if any, party banner he'd run for re-election under.

"I like being an independent, so that's definitely a possibility," Lieberman told the U.S. broadcaster. "But I'd say all options are open," adding that while running as a Republican was "unlikely," he wouldn't "foreclose any possibility.

"I've reached the stage in my career where I'm not measuring every step I take based on how it's going to affect the next election. I think if you do that, you end up compromising the quality of your service."

The comments came after Lieberman once again enraged Democrats by threatening to join a Republican filibuster of a Senate compromise on healthcare reform, even after negotiators acknowledged his complaints about a proposed government-run "public option" health plan and dropped it in favor of an expansion of Medicare.

Lieberman surprised Senate leaders Sunday when he said he would not support the Medicare move either.