Democrats won it all in California this week – prevailing on new taxes and other major ballot measures and apparently achieving supermajorities in both legislative houses and, at least on paper, a free hand to do whatever they wish on anything.

The reality, however, is somewhat more nuanced.

Yes, voters passed Proposition 30, Gov. Jerry Brown's sales and income tax increase, and he hailed it as "a vote of confidence" that the chronically imbalanced state budget will finally become deficit-free.

However, it's uncertain that Proposition 30 will generate as much money as the 2012-13 budget assumes, and even if it does, other budget holes are emerging.

Furthermore, the new taxes are temporary, while much of the spending they finance is permanent, and the measure makes California even more dependent on a few high-income taxpayers, which makes revenues even more volatile.

While praising Proposition 30's effect on the budget, the Standard & Poor's credit rating house warned about volatility and potential problems when the taxes expire – just before Brown retires if he wins another term.

However, some already speculate, if the state needs more revenue to finance the budget or to increase spending, couldn't those Democratic supermajorities just enact more taxes?

Yes, in theory. But with two Democratic senators leaving for Congress, another likely to leave for a seat on the Los Angeles City Council, special elections to fill their seats, Assembly members running for Senate vacancies and more special elections to fill their seats, it's not certain when Democrats will actually have two-thirds majorities of sitting members.

Moreover, not all Democrats, especially those from swing districts, want to vote for more taxes. Republicans are likely to regain at least one Senate seat in 2014, and Brown appears to be warning his partisan colleagues not to get carried away with their newly won hegemony.

"Let's take this win and not snatch defeat from the jaws of victory," Brown said Wednesday afternoon, adding, "Desires are endless. I vow to cut them down."

Earlier, he told a television interviewer, "The challenge is what can we do with it? Can we earn and maintain the people's trust?"

One thing the Democratic supermajorities could do without Brown, whenever they are mustered, is place constitutional amendments on the ballot. Many Democratic politicians and their labor union allies would like nothing better than to repeal, or at least modify, Proposition 13, the 1978- vintage property tax limit.

That would take a constitutional amendment approved by voters, and it won't happen immediately.

But if the new taxes approved Tuesday don't supply enough money to satisfy their constituents' needs and wants, Democratic legislators may be tempted to take on Proposition 13, for many the holy grail.

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