U.S. Sen. Claire McCaskill, D-Mo., said today that she’s not ready to endorse a candidate for president, and left it up in the air whether she would before Missouri’s Feb. 5 primary.

But as she has for months, McCaskill couldn’t resist offering a hint of where her sentiments may be. “I’m torn between my heart and my head,” she said during a meeting with Post-Dispatch editorial writers and this reporter.

Her heart is with a particular candidate, she continued, while her head tells her it might be best to stay uncommitted and on the bench, especially since she works with both Sens. Barack Obama , D-Ill.(who McCaskill long has been rumored to favor) and Hillary Rodham Clinton, D-N.Y.

McCaskill has told reporters that Obama’s campaign called her at home Thursday night to ask for campaign suggestions about Missouri’s primary. She emphasized that she’d offer the same advice if asked by the Clinton campaign.

“These are two people I continue to work with,” she said, adding that one will likely end up president, while the other will remain a colleague in the Senate. McCaskill said she needs to maintain a good relationship with both.

But then, McCaskill went on to compare the duo’s rivalry to her failed 2004 bid for governor against then-one-term Secretary of State Matt Blunt, a Republican.

“I’ve seen that movie before,” McCaskill said, likening her old predicament to that of Clinton now.

“Remember, I was ready to be governor from Day One, and I was running against someone who ‘wasn’t ready,’ ” McCaskill recalled.

But she added that voters didn’t embrace her more-experienced pitch.

“At a certain point in time, voters just want change,” McCaskill observed.

As for Clinton-Obama, McCaskill said, “It’s difficult for Sen. Clinton that she lost the women,” referring to exit polls showing that a larger share went for Obama.

However, McCaskill offered up a devastatingly direct assessment of the third top-tier Democratic contender, former Sen. John Edwards, D-N.C.

“I don’t think John Edwards will have the ability to make it to Feb. 5,” McCaskill said.

MEANWHILE:

State Auditor Susan Montee, a McCaskill buddy, called in from New Hampshire, where Montee is stumping for Obama.

Montee flew in Thursday, and plans to remain in the Granite State until early Wednesday (the morning after the primary), when she’ll fly back to Missouri for the opening of the Legislature.

“I’m really excited, and it’s really cold,” said Montee. “It’s like 2 degrees outside today, so I elected to phone bank.”

Because of Obama’s Iowa victory, the phones are ringing off the hook Friday, as people flock to offer their support and assistance, she added. “Clearly, the results in Iowa are certainly going to have a big influence on what’s happening here.”