This is an update to correct the name of the fiscal watchdog group the Committee for a Responsible Federal Budget.

WASHINGTON (MarketWatch) — Ted Cruz is not a reasonable alternative to Donald Trump.

Establishment Republicans, fearing that Donald Trump’s nomination as the party’s presidential candidate would lead to disastrous losses for Republicans in November’s election, are grasping for an alternative.

Unfortunately for them, the only other candidate who’s received any significant voter support is Texas Sen. Ted Cruz. And Ted Cruz is as far from mainstream Republicanism as Donald Trump is.

Although some establishment Republicans back Cruz, most don’t. He’s gotten the endorsements of five of the 34 Republican governors and just two of the 53 Republican senators not named Cruz.

There’s a reason most Republican governors, senators and congressmen haven’t endorsed either Trump or Cruz. For the establishment GOP, both are nightmares, because each appeals to small but vocal factions of the party. Most probably neither could be elected, and, if one was, he likely couldn’t govern.

Wisconsin hands defeat to presidential frontrunners

Which, of course, is why the party’s establishment is clinging to the idea of a deadlocked convention that would ultimately spurn both Trump and Cruz and nominate a more palatable (but far from invincible) mainstream candidate, possibly Paul Ryan, John Kasich, Mitt Romney or Marco Rubio.

What sets Cruz apart from these other Republicans?

Ted Cruz lies at the far-right end of the political spectrum, far more conservative than the typical Republican senator. Poole, Rosenthal & Hare

For starters, Cruz is extremely conservative, even by Republican standards. He’s on the far right of a party that is moving to the right. He would be the most conservative president since Calvin Coolidge.

Cruz is one of the most conservative senators today. He earned a perfect 100 voting record from the American Conservative Union (the average Republican senator scored 79) and a nearly perfect voting record from the Club for Growth and the National Taxpayers Union. Political scientists Keith Poole, Howard Rosenthal and Christopher Hare also rank Cruz as one of the most conservative senators based on their analysis of every roll call vote taken.

Cruz’s strategy during the 2016 primaries has been to position himself as the most conservative candidate, appealing to both ultraconservatives and to evangelicals. That plan has worked (at least he’s still in the race). He’s won nine states and 514 delegates, compared with 19 states and 740 delegates for Trump. But polls show that Cruz would lose the general election to either Democrat — Hillary Clinton or Bernie Sanders — because he’s too conservative for general-election voters.

Cruz has benefited from being in Trump’s shadow this campaign season. Trump says a lot of crazy things, but few people have noticed that Cruz says lots of crazy things too. If Cruz gets the nomination, more people will start to pay attention to his positions on the issues.

The economy

Cruz doubles down all the failed trickle-down policies of the past 36 years that were supposed to supercharge our economy, but which ended up enriching the billionaires and leaving the typical family treading water economically.

Most Republicans want a smaller government, but Cruz’s budget plans go much further than the budgets approved by the Republicans in the House and Senate. Despite Cruz’s professed concern about the federal debt, the deficits would explode if his plans were adopted.

Even the most favorable analysis suggests that his flat-tax reform plan would starve the government of revenue, adding at least $3 trillion and as much as $21 trillion to the debt over 10 years. He hasn’t called for nearly enough spending cuts to balance the budget, even though he says he’s in favor of a constitutional requirement that the budget be balanced. By one account, to get to a balanced budget, Cruz’s tax plan would require spending to be cut in half, or for the economy to grow four times faster over the next decade. Neither is going to happen.

The bipartisan fiscal watchdog group, the Committee for a Responsible Federal Budget, says the federal debt would rise to 131% of gross domestic product in a decade, up from the 86% estimated under current law. Cruz’s budget has larger deficits than Obama’s does.

The middle-of-the-road Tax Policy Center estimates the higher deficits created by Cruz’s tax cuts would crowd out private investment and offset most or all of the pro-growth effects of lower and simpler taxes. So much for trickle down.

And, of course, the tax cuts would exacerbate the inequality that’s polarizing the nation along class lines, because most of the benefits would go to those who are already fabulously wealthy. But that doesn’t stop Cruz from cynically campaigning on a promise to stop favoring the 1%, like Barack Obama and the Democrats do.

But wait! There are more crazy ideas. One is that Cruz advocates a return to the gold standard, a policy that would lead to more deflation, recessions and impoverishment of the debtor class.

Read:Gold is the pile of poker chips in the next global crisis

Foreign policy

Like Trump, Cruz’s views on foreign policy are incoherent. Cruz wants a strong military, but he doesn’t want to use it anywhere except in the Middle East, where he wants to carpet bomb Syria and Iraq to find out if “sand glows in the dark,” mistakenly assuming that more bombing and instability will help destroy ISIS and other terrorist groups that feed on the hatred of the West that bombing and political instability breed.

Cruz, like Trump, would build a big wall to keep the illegal Mexicans out.

A Christian nation

All of our presidents have been Christians — nominally, at least — but we’ve never had a radical Christian as president.

Cruz would ban Muslim refugees but allow Christians to enter. He wants the police to “patrol and secure” neighborhoods where Muslims live. He claims, wrongly, that Christians are never terrorists.

It’s all part of Cruz’s embrace of a fringe Christian group that wants true-believing Christians to have dominion over not only over America’s government, but also all of our other institutions.

Cruz’s father has said he believes God has chosen his son to save the nation from unbelievers, and by all appearances Cruz believes it, too. Cruz would be America’s ayatollah, enshrining “Christian values” into the law.

Getting along

There’s one final reason that even mainstream Republicans recoil at the idea of Cruz as president: He’s unlikable. He doesn’t get along well with co-workers and he never has. Just Google “why do people hate Cruz,” and you’ll see 58 million reasons.

Trump had it right when he said: “Look, the truth is, he’s a nasty guy. Nobody likes him. Nobody in Congress likes him. Nobody likes him anywhere once they get to know him. ... He’s got an edge that’s not good. You can’t make deals with people like that and it’s not a good thing. It’s not a good thing for the country. Very nasty guy.”

A president needs to employ both carrots and sticks to get things done, but Cruz only has a stick. A president needs to work with Congress, with governors, mayors and local leaders, with federal agencies, with foreign leaders, with leaders from the private sector. Cruz is arrogant and bombastic, and he’s convinced that he’s always right.

Cruz’s 21-hour filibuster that led to the pointless 16-day shutdown of the federal government in 2013 was irritating enough. Now imagine four years of Cruz reading “Green Eggs and Ham” to us and demanding that he get his way or else he’ll shut everything down.

Republicans have a problem. Which means all of us have a problem.