[dragonwriter]

> They stand a good chance of yet another Republican losing to Feinstein, if they all vote for the Republican

In a primary election, there is likely to be more than one Republican, and the opening of the primary system means that, instead of the Republican with most support from Republican activists being moved forward to the general election, in the absence of substantial cross-major-party-voting or massive supermajority Democratic primary turnout (unlikely in a statewide primary), the Republican with the most appeal to Republicans and Republican leaning independents voting in the primary will move forward.

The very same changes to the primary system that you are going on about are exactly why it doesn't make much sense for Republicans to cross-party vote, since the problem that has made them noncompetitive in statewide general elections is mitigated in the new primary system and, unlike registration-switching in the old partisan-primary system, cross-party voting actually means your party is less likely to even have a candidate in the general.

As a California Democrat, I'd love it if Republicans followed your plan, because I'd like nothing more than a D v. D general election.

[dllthomas]

"Republicans are more likely to nominate a candidate that is broadly appealing" is a reasonable theory, and to the degree that this dynamic dominates it's true that it would lend the Republicans more of a chance; if that's enough to make a difference, the Republicans should indeed focus on their own candidate. The one data point we have so far lost 38-61.

"As a California Democrat, I'd love it if Republicans followed your plan, because I'd like nothing more than a D v. D general election."

That's precisely why it might work. Democrats should like it for the reason you specified; Republicans should like it if there is someone they prefer to Feinstein. If enough of both get on board, it happens.

[dllthomas]

Note also that it doesn't necessarily take Republican involvement - that just helps. If every Democrat who was going to vote for Feinstein had instead flipped a coin, and voted for her on a heads and some particular other Dem on a tails, it would have been Dem vs. Dem in 2012.