Barbara Bush has moved from her former stance that there have been too many Bushes in the White house.
She was right the first time. None of the Bush presidents has been a truly conservative force (in fact, no 21 century Republican presidential candidate has been conservative).
The Bush presidents (and every Republican candidate since) have been generally socially conservative - but fiscally they've been "Democrat light". And just like light beer, the Republican candidates aren't really exciting to anyone. Democrats wouldn't (generally) consider voting for a Republican, Independents see Democrat and Democrat Light, and if they're inclined to vote for someone other than an Independent candidate they'll probably vote for the Democrat. Republicans see Poisoned Kool-Aid and Possibly Poisoned Kool-Aid, and they aren't really certain they want to partake of either. Some of them will choose to just not drink either kool-aid, leading to low voter turnout. Unfortunately, that's not how it works. Once the election is over, the voters have chosen one or the other, and every has to take a drink.
What you need is a fiscally conservative candidate who can tell the MSM that most social issues belong at the state and local level and make it stick.
Given a choice of Poisoned Kool-Aid and Possibly Poisoned Kool-Aid, I'll pick the Kool-Aid that is only possibly poisoned. But I really just want water.