Cross two more names off the list of 3M Co insiders who could succeed George Buckley as chief executive if he steps down when he turns 65 next year.

The diversified U.S. manufacturer, which has a tradition of ending its CEOs' contracts at that age, said on Friday that Executive Vice President Jean Lobey, 58, and Senior Vice President Robert MacDonald, 60, will retire in the next two months.

Those looming departures, along with Chief Financial Officer Patrick Campbell's upcoming retirement, could signal some of the top brass at the maker of products ranging from Post-It notes to optical films used in flat-panel televisions no longer think they have a shot at the corner office.

Given that you now have three executives leaving in a relatively short period of time, there is a possibility that there was some thought that they may have had a chance at that position, which is not the case at this point, said Jeff Windau, an analyst at Edward Jones in St. Louis.

The company has named replacements from within 3M for all three executives, who are due to retire in May and June.

Julie Bushman will succeed Lobey, overseeing the safety, security and protection business, Ian Hardgrove will replace MacDonald, heading marketing and sales, and David Meline will take over from Campbell.

CEO WANTS TO STAY

Buckley, who joined 3M as CEO from Brunswick Corp in 2005, has made no secret of his desire to stay on past his contract's expiration date in February 2012.

I love being the CEO of 3M, Buckley told investors in March. I'm not the guy that has the choice on whether I stay or not.

That choice lies with the company's 10-member board of directors -- which Buckley has a seat on. The board is expected to choose whether to break with its tradition and extend Buckley's contract in the coming months.

If you have a CEO that is excited, and I think doing a pretty terrific job, why not keep him on if he wants to stay? said Adam Fleck, an equity analyst with Morningstar in Chicago.

3M shares were up 1 cent at $93.20 on the New York Stock Exchange.

Both Buckley and his predecessor James McNerney, a former General Electric Co executive who now heads Boeing Co , were brought in from the outside. McNerney, who joined in 2000, is credited with vastly improving 3M's profit margins at a time when they were low while analysts say Buckley's mark on the company has been a resurgence of research.

But analysts expect the 109-year old company, which employs more than 80,000 people worldwide, to choose its next leader from among its current executive ranks.

Even with the current round of retirements, 3M has a deep bench of executives with decades of experience at the company, including Inge Thulin, executive vice president of international operations and Brad Sauer, executive vice president of its health care unit.

If you started to see a lot of the vice president heads of the divisions starting to say, 'I'm out of here,' that would be more concerning to me, Fleck said. It's encouraging to read reports that the company wants to return to promoting from within.

(Reporting by Scott Malone; Editing by Phil Berlowitz)