Presidents Ronald Reagan and Donald Trump have inspired overwhelming loyalty from their party's rank and file, probably more than any other modern president. But not in the same way.

Reagan articulated an optimistic philosophy of smaller government, lower taxes, anti-communism and traditional values that reflected what Republican voters believed. Trump has reshaped the Republican core, conjuring an anti-trade, anti-immigration party that welcomes racists and winks at dictators. To be sure, not all Republicans buy into Trump's grim worldview, but polls show that almost 90 percent of Republicans are Trump supporters.

"Trump's control over the grassroots base is bigger even than Reagan's," said Vin Weber, a major Republican player and former congressman who came to Washington in 1981 when Reagan arrived. "It's very personal."

There are prominent Republicans who are troubled by the cult-like following of a dark and deceitful president.

One of them is Mitch Daniels, who boasts a distinguished Republican pedigree. He was Reagan's chief political adviser, director of the Office of Management and Budget under President George W. Bush and a successful two-term Indiana governor. Before the rise of Trump, he would have been considered by knowledgeable Republicans, conservatives and moderates alike, to be a top-quality candidate for president.

But now he says this: "I feel homeless."

The options for disaffected Republicans are bad or worse: voting for Democrats, taking on Trump or biding time until Jan. 21, 2021.

The conservative columnist George Will wrote in The Washington Post last month that Republicans should vote for Democrats this fall to check Trump's excesses and "affirm the nation's honor." His point was reinforced last week when Republican congressmen, notably Jim Jordan of Ohio and Trey Gowdy of South Carolina, trotted out false accusations to attack the Federal Bureau of Investigation and smear Deputy Attorney General Rod Rosenstein in an effort to protect Trump and undermine the investigation into Russia's meddling in the 2016 election.

Another option is to challenge Trump. Yet most Republicans are intimidated by the president's power to mobilize his supporters. Authentic conservatives like Sen. Jeff Flake of Arizona and Rep. Mark Sanford of South Carolina were driven from office by Republican voters for merely questioning the president's behavior and rhetoric.

Republican activist Bill Kristol says that conservatives should challenge Trump for the 2020 nomination to re-establish the economic, national-security and moral principles of the Republican Party. Kristol argues that Trump's support among the rank and file will diminish over time. Neither Flake nor Sen. Ben Sasse, a Nebraska conservative, have ruled out taking on the incumbent in 2020.

Ohio Gov. John Kasich, who was beaten for the nomination by Trump in 2016, and his political adviser, John Weaver, are testing the waters for another run. A few Republicans think that the 2012 presidential nominee, Mitt Romney, who is likely to become a Utah senator after November, should lead the opposition. But don't bet your salary on that development.

Savvy Republicans in Iowa and New Hampshire, including some who oppose Trump, are nearly unanimous in their conviction that Trump would be unbeatable today in Republican contests in their states. In New Hampshire, one of the states where Kasich ran strongly in 2016, a leading Republican candidate for an open House seat is State Sen. Andy Sanborn. Last week Sanborn sent out an appeal urging Republicans to regard their vote as a referendum on Trump. "A Never-Trumper itching to primary President Trump in 2020, Kasich is hoping conservatives like me fail," his letter said.

The third bad option for alienated Republicans is to wait it out while working to lay a foundation for a different kind of party. The 2016 election, Daniels said, showed "how quickly politics can change; maybe it can change again." 

As a Hoosier and now president of Purdue University, Daniels is a basketball fanatic. He said Republicans could emulate the Philadelphia 76ers, the professional basketball team that suffered through three miserable years with the worst record in the National Basketball Association as they tried to build for the future. "Trust the process," the team urged its followers.

This year they were a winning playoff team, though not a serious contender for the championship. Trusting a political process for the next 2 1/2 years doesn't seem very appealing either. 

Albert R. Hunt is a Bloomberg Opinion columnist.