A referendum is a particularly tricky bit of political activity. And Proposition 40, which will appear on the November ballot, is even trickier than usual.

A referendum is like an initiative in reverse. Initiatives ask voters to enact either legislation or a constitutional amendment, so those who agree with an initiative measure vote "yes."

However, a referendum is a way of repealing something already in law and voters who support repeal are asked to vote "no."

As potentially confusing as that may be, Proposition 40 is even trickier because it proposes not to repeal a law passed by the Legislature, but rather new state Senate maps drawn by a new independent redistricting commission. And the Republican Party, which sponsored it to seek a "no" verdict from voters, now says it won't mount a campaign.

Nevertheless, Proposition 40 remains on the ballot, and without campaigns to frame its effect, there's no telling how voters will react.

With the trust quotient among voters about politics at an all-time low, it's conceivable that they will reflexively vote "no" and thus repeal those 40 new state Senate districts.

Were that to occur, the state Supreme Court would draw new Senate districts itself, under the section of the constitution that created the independent commission. And chances are strong that the court would reinstate the maps that voters had rejected, or something very close to them.

Elections will be held this year in 20 Senate districts – those with even numbers – and Capitol insiders are watching four of them to learn whether Democrats, who hold 25 of the 40 seats now, will increase their majority to 27, or two-thirds.

Gaining 27 seats would give Democrats the power to do things they can't do now by themselves, such as vote for tax increases, to place constitutional amendments on the ballot and to enact so-called "urgency bills."

That would isolate Assembly Republicans, who will retain more than a third of its seats, which is why the GOP sponsored the referendum in the first place.

Democrats' chances of picking up two or more Senate seats this year are probably well over 50-50, but it's not a certainty, and candidates' legislative votes are being watched very closely for potential campaign fodder.

That's probably why Democratic Sen. Fran Pavley detoured from the party line to vote against the very controversial bullet train. Her newly redrawn 27th Senate District in the Southern California suburbs is more conservative than her liberal voting record.

Republican Assemblyman Bill Berryhill, running in a tossup state Senate district in the San Joaquin Valley, voted against the bullet train while his opponent, Democratic Assemblywoman Cathleen Galgiani, voted for it.

How will that be played?

Somehow, certainly, in the Senate power struggle.

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