Author Matt Grossmann argues that the Republican Party hasn't gotten their agenda through the states because most people just don't like their agenda:
Where Republicans gained policy victories, the consequences on the ground were surprisingly limited. Abortion and gun laws changed in every state, but not enough for Republican control to produce changes in state abortion numbers or crime rates. Republicans opposed raising income taxes on the rich, but not enough to exacerbate inequality or accelerate economic growth in their states. They promoted traditional families, but not enough to reduce divorces or increase births.
Republicans did not fail for lack of an ideological agenda. Their state legislative caucuses moved steadily rightward, replacing moderates with far-right Republicans. They nationalized state policymaking, often joining forces in state efforts to counter federal initiatives. They developed cookie-cutter legislation by organizing their allied interest groups and legislators.
But they faced the same problem of conservative parties worldwide: Translating a philosophy of small government and traditionalism into major cuts to public services is quite unpopular. The public sides with protesting teachers once schools are on the chopping block. Expanding health care draws far more support than cutting programs. Republican governors would rather announce new prekindergarten efforts than shutter nursing homes. Republican legislators reconsider their most ambitious tax promises once the consequences are clear. Unlike at the federal level, politicians in the states have to avoid deficits — meaning the service consequences of tax cuts are clear to voters. Since Republicans came to power mostly in the states that already had the smallest public sectors, there was less room to cut.
Does this mean Republicans will stop trying to impose idealistic right-wing policies? Don't be silly; ideologues never listen to reason. But it does mean that maybe our policies can win elections, now that people have seen theirs.