E.J. Dionne Jr., writing in the Wash Post (Jan. 4, 2004):

Here's what being a senator means when you run for president:

It means you have thousands of votes on the record that can be distorted in a heartbeat. Sen. John McCain learned this during the Republican primaries in 2000 when a radio ad in New York accused him of voting against money for a cancer research center in the state. The ad, run in support of George W. Bush, picked out a vote McCain had cast against a huge spending bill that included the cancer money. McCain had voted many times in favor of cancer research spending. It didn't matter. He was trashed.

Sometimes, being a senator and running for president means always having to say you're sorry for not being a governor. In 1996, Richard Lugar, one of the most respected members of the Senate, ran what now looks like a prescient Republican primary campaign highlighting the dangers of terrorism. No one paid much attention. At one point in 1995, Lugar found himself on "Larry King Live" trying to describe why a senator with extensive foreign policy experience might have the best training for the job. "Governors and mayors can handle a lot of things in this country," said Lugar, but only the president "can be commander in chief. . . . So we'd better talk about that first, as a prime qualification." Lugar, himself a former mayor, won admiration -- but few votes.

Legislators are sausage makers working in an unruly factory. The very elements that are fundamental to serving in Congress -- the arts of compromise and cajoling, the finality of the yes or no vote -- leave members vulnerable as presidential candidates. As a rule, politicians hate binary choices. They like words such as "but," "both," "and," "maybe" and "in addition to." But many "yes/no" votes require choosing one bad over another, or between two imperfect goods.

Ask Bob Dole. He's one senator in recent times who managed to survive the primaries. His standing as Republican Senate leader made him reasonably famous -- and easy to hold accountable for the actions of others in Congress. In the 1996 campaign, Bill Clinton tied Dole to House Speaker Newt Gingrich, blaming the pair for the 1995 government shutdown and for cuts in "Medicare, Medicaid, education and the environment." That was it for Dole.