When Pennsylvania Senator Arlen Specter switched to the Democratic Party earlier this year, that which was probably the main reason for his move was a very practical one: he had concluded that he could not win next year's Republican primary.
His new party's top leadership, including President Obama, Vice President Biden and Pennsylvania Governor Ed Rendell, welcomed him aboard. However, Specter is getting less respect, further down the Democratic ladder.
What has long been expected has now come to pass; Specter will be opposed in the Democratic primary by at least one congressman.
The Democratic Party's resurgence since 2006 has largely been based on opposition to Gulf War Two. That party has made a special effort to recruit military veterans as candidates. Thirty-some years earlier, opposition to the Vietnam War, which came primarily, but not exclusively, from the Democratic Party, gave the Democrats an anti-military image, that harmed its electoral prospects, as the end-game of the Cold War came on, during the late 1970s and the 1980s.
The message that Democrats aim to project, that they support and understand the military, is carried by such veterans as Representative Joe Sestak, the congressman who is running against Specter. Sestak, a Naval Academy alum who reached the rank of rear admiral, has represented a district in the western suburbs of Philadelphia since 2007.
Only Specter can know whether he expected his new party to give him a clear shot at the general election. But I can't help but think that, between his loss of seniority on his committees, and this intra-party challenge, his switch is not turning out as well as he hoped.