Credit NBC with putting together back-to-back lures for political junkies.

Sarah Palin's long-rumored appearance on "Saturday Night Live" this weekend is a done deal. And folks watching for that can just keep their sets tuned to the network when they go to bed, because the "must-see" TV on Sunday morning will be Colin Powell's appearance -- announced today -- on NBC's "Meet the Press."

Credit Powell with having starred in this campaign's longest-running guessing game: Would the famed former Army general and former secretary of state under President Bush, who flirted with seeking the Republican presidential nomination in 1996, cross party lines and publicly back Barack Obama?

The buzz today is that he will do so in the Sunday show spotlight. If so, it will end speculation that began more than a year ago -- and periodically would reignite.

In an interview on "Meet" in June, 2007, Powell created a stir when he pointedly declined to commit to endorsing whomever might emerge as the GOP presidential nominee. This year, his every word and action have been closely watched -- and usually interpreted as indicatin of a pro-Obama slant (see here, here, and here). One report --off-the-mark, as it turned out -- suggested Powell would deliver a dramatic speech at the Democratic National Convention on Obama's behalf.

If anything, anything less than a Powell embrace of Obama this weekend would be a letdown for the Democrat. As for its potential benefit, here's what Jonathan Martin astutely has to say at Politico.com:

It wouldn't exactly be a profile in courage on Powell's part to get behind Obama now, but it would help rehabiliate his post-Iraq image in some quarters. And it would be the sort of validating endorsement -- Republican, military man, well-known elder statesman -- that the Democrats would trumpet in the closing days of the campaign to assure voters that Obama is a "safe" pick.

-- Don Frederick