Given her record, people had expected a weak, boring package from her committee. But Lincoln came up with rules that were tougher than anyone had expected, requiring derivatives to be traded on public exchanges so investors could compare prices. The banks hate this idea, possibly because it will drive down their profits.

For sure because it will drive down their profits.

“The bridge of cooperation has been washed out,” said Republican Pat Roberts of Kansas crankily, as Lincoln nudged the bill through committee. He also warned that the senators were “smothering ourselves in the milk of human kindness and hoping it doesn’t curdle,” nailing down first place in the hotly contested Senate metaphor-making competition.

It was the first time Lincoln seemed like an interesting political figure since 1998, when, at 38, she became the youngest woman ever elected to the United States Senate. Now her seat is in jeopardy. Conservatives smell blood. The left is backing her opponent in a primary next month. Bill Clinton expressed his support by saying, “I wouldn’t be surprised to see her coming back from the dead.” Which is really not what you want to hear from the former president while you’re out fund-raising.

So it’s pretty easy to figure out what caused Lincoln’s hard line on financial reform. She is tacking to the left the same way John McCain, struggling in a hot primary in Arizona against a Tea Party-type opponent, is tacking to the right.

But let’s give her credit for never having gotten desperate enough to claim that cars full of illegal immigrants were “intentionally causing crashes on the freeway.” Unlike some former mavericks we could mention.

Americans are certainly in the market for some leadership on the subject of derivatives. It’s hard to even figure out how to worry about them, since we have no clue exactly what they are, beyond bets on whether prices will go up or down.