Democrats in the U.S. Senate probably are at least temporarily on a solid legal footing in their decision not to accept the man appointed to fill the vacant Senate seat left by President-elect Barack Obama.

The question is how far they want to push an issue that puts political infighting on the front burner and distracts from far more important national business.

Roland Burris, the former attorney general of Illinois, was appointed by Illinois Gov. Rod Blagojevich last week to fill Obama’s Senate seat. Blagojevich faces corruption charges based on conversations in which he appeared to be seeking some financial or political reward in exchange for the Senate appointment. Because of those allegations, Blagojevich has lost most of his credibility as an elected official, but he remains in office and presumably has not lost his authority to appoint Obama’s replacement.

Senate leaders want to distance themselves from any Blagojevich wrongdoing, and, therefore are refusing to accept his appointee. The Illinois secretary of state has given them an additional “out” by refusing to sign the formal appointment papers that the Senate requires to seat an appointee.

Burris is undeterred with the controversial nature of his appointment and is determined to take his seat regardless of how marginalized he will be if he is allowed to serve. Legal action is likely.

It’s understandable that Democrats want to punish Blagojevich for the embarrassment he has caused the party, but dragging this situation out doesn’t benefit either the party or the nation. If Burris is not seated, what’s to stop Blagojevich from picking someone whom Senate leaders find even more objectionable? And what kind of precedent does the rejection set? What if Republicans were in the majority and choosing to reject a Democratic appointee?

In the meantime, Senate Democrats are being criticized for refusing to accept the man who would be the only black member of the Senate, and the political infighting is casting an unflattering light on the new party in power.

Even if Blagojevich is impeached and/or removed from office, there doesn’t seem to be any legal basis to cancel actions he took or decisions he made while he was the duly elected governor. If Burris lacks the integrity or intelligence to be a good representative for Illinois, voters can address that problem if he seeks re-election.

At this point, Democratic Senate leaders have a choice. They can either spend weeks or months fighting this public and unflattering battle not to seat Burris or they can seat the man and get on with business that is of far more importance to the country.

The choice may be hard for Senate leaders to swallow but it seems pretty clear.