At their core, political primaries are about finding the strongest nominee for a party to put forward in the general election. For Pennsylvania Democrats, who have two capable candidates with extensive voting records, this is an especially critical choice.
It is critical because the Republicans, who have their own primary decision to make, are likely to nominate former congressman Patrick Toomey, a well-funded and well-known staunch conservative who is pivotal to the national party's game plan for taking back the Senate.
That's why Democrats on May 18 need to choose wisely. That's why Democrats must nominate Arlen Specter.
The veteran incumbent from Philadelphia has represented Pennsylvania in Washington for five terms - and almost all of the time as a moderate Republican. One year ago this week he joined the Democratic Party at a crucial moment for the Obama administration and, to the chagrin of his new across-the-aisle allies, added a key vote to the Senate majority but also maintained a streak of independence.
Although the Post-Gazette has had its differences over the years with Mr. Specter, his knowledge of the state's needs, his ability to command respect on Capitol Hill and his voice for the brand of civil discourse that is too rare in America today have few rivals.
The senator's challenger is also a distinguished Democrat. Rep. Joe Sestak of Delaware County won election to Congress in 2006 and has been a reliable liberal vote for his party's agenda. A retired three-star admiral, Mr. Sestak is the former commander of an aircraft battle group and cares deeply about restoring trust in Washington.
In a different political year, his true-blue liberalism might be just the ticket for the Democratic Party. But in 2010, with an insurgent challenge to claim the seat from the right and with grass-roots tea party activists railing against the role of government, whoever hopes to become Pennsylvania's next senator will need to win votes from the center. Arlen Specter has a long record of being that kind of vote-getter.
In a Quinnipiac University poll this month, 60 percent of likely Democratic voters had a favorable view of the senator, against 26 percent who felt unfavorable; only 12 percent said they were unsure. As to Mr. Sestak, only 33 percent of his party's likely voters viewed him favorably, while 6 percent were unfavorable and a troublesome 58 percent said they hadn't heard enough to form an opinion. If Mr. Sestak were the nominee, that lack of knowledge and certainty among Pennsylvania's majority party could doom his candidacy in November.
While Joe Sestak tries to portray himself as the genuine article, Arlen Specter is the real deal - with a demonstrated record of service for Pennsylvania. He'd be the stronger candidate for Democrats in the fall, and he has the Post-Gazette endorsement.