Barbara Boxer's 18-year career as a U.S. senator has resembled a "Perils of Pauline" movie serial, for those old enough to remember.

Boxer always seems to be on the verge of losing her senatorial seat but, so far at least, has always managed to win another six-year term, thanks either to her pluck (her version), massive rescue efforts by the Democratic Party, and/or the ineptitude of her Republican foes.

Boxer has escaped three times. But her unrepentant liberalism, several notches to the left of center, and her penchant for creating sparks, such as her inexplicable upbraiding of an Army general for referring to her as "ma'am" and not "senator" during a committee hearing, make re-election problematic.

Recent polls indicate that her re-election numbers are well below the magic 50 percent number, regardless of which of the three would-be Republican challengers she'd face.

A new Rasmussen poll, for instance, found that her re-election support is in the mid-40 percent range regardless of whether she's matched against former Hewlett-Packard honcho Carly Fiorina, former Congressman Tom Campbell or state Assemblyman Chuck DeVore.

"The fact that Boxer's support has been stuck in the mid-40s for several surveys no matter which Republican she is matched against continues to suggest that the race for now is about her rather than about those who are running against her," Rasmussen Reports states.

Boxer's been there before, running poorly in pre-election polls but has always managed to win, sometimes by a little, sometimes by a lot. What puts her on the endangered list this year is the very sour attitude of voters toward all incumbents, regardless of party.

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