Cruz and his House allies could grow their numbers. But without leadership backing, they can’t unify their caucuses. The best they can do a cause a temporary shutdown by preventing Congress from passing a spending bill.

But such a result wouldn’t force resistant Republicans and Democrats to take up the banner of defunding Planned Parenthood. It would only force congressional Republicans to rely on Democratic votes to keep the government open.

In other words, instead of passing a Republican bill that cuts domestic spending, putting maximum pressure on President Obama to accept at least some of those cuts, congressional Democrats will be able to force Republicans into accepting either a budgetary status quo or further relief from the “sequester” cuts in the 2011 budget deal.