The new voter registration statistics are bad news for Republicans, and the closer you look, the worse it becomes for the GOP.

When the Secretary of State released the new report the other day, plenty of people noted that statewide Republican registration is now at an all-time low of 30.4. But even more striking is GOP registration in the 20 coastal counties (those that touch either the Pacific Ocean or San Francisco Bay). It’s down to 27 percent.

Twenty years ago, Republican registration in the coastal counties was almost 36 percent. It was 32 percent, fully five points higher than it is today, as recently as 2003, when Republicans flexed their muscle by booting out a Democratic governor and electing a moderate who, it was widely said at the time, could broaden the party’s appeal. By contrast, Republican registration in the 38 inland counties has held fairly steady. Twenty years ago it was 41 percent; today it is 39 percent.

This is more than just geography. Coastal California is important politically because it’s where the votes are. The 20 coastal counties cast more than 71 percent of the total vote in the 2010 election.

What’s more, Democrats dominate the coast far more than Republicans lord over the inland counties. There are nine counties, all but one of them coastal, where a majority of registered voters are Democrats. They contain 6.7 million voters. Here is the number of counties, coastal or inland, where Republicans are a majority: zero. (Even in more conservative areas of the state, Republicans can muster only a plurality, not a majority.)

If you can’t win, or at least do respectably, among people who have an easy drive to the beach, you cannot win statewide in California. The new registration numbers only re-emphasize that the state’s east-west divide, still a relatively new phenomenon, is a body blow to Republicans.