By some measures of conventional Washington wisdom, Ms. Snowe might
gain some strategic advantage by withholding her support in the
committee vote, knowing that Democrats will advance the bill to the
floor anyway and then have to continue working to win her over.

By other calculations,  a vote on Tuesday would send a loud signal to
Congress and to the nation that Ms. Snowe is willing to stand by the
bill, which she had a strong hand in writing over months of intense
bipartisan negotiation.