Forty or 50 years ago, the very thought of Dwight Eisenhower or Richard Nixon being too liberal for the Republican Party would have been hard to fathom. But what was considered conservative in the GOP of the 1950s, '60s or '70s would be considered centrist or moderate today. The power that extreme wingnuts exert on the modern GOP has been obvious during recent events in Congress, especially the ongoing debates surrounding the Affordable Care Act of 2010. Catering to the Tea Party and the GOP’s extremist base, Republicans shut down the government for the first time since 1995-1996.

The fact that killing Obamacare is such an obsession for House and Senate Republicans is ironic in light of the fact that in the past, many Republicans (including Nixon, Sen. Bob Dole and Mitt Romney) were proponents of universal healthcare via the private sector and proposed ideas similar to Obamacare. In fact, a criticism many liberals and progressives have had of Obamacare is that it is too close to Republican ideas of the past. So House Republicans have, in effect, been railing against what used to be a Republican idea.

House Republicans also pandered to the Tea Party when, on September 19, they pushed through a bill that calls for slashing billions of dollars from the food stamp program during the worst economic conditions since the Great Depression. The bill, which passed the house 217-210, was passed largely along party lines: only 15 Republicans voted against it, and not one House Democrat voted for it. In the past, that bill would have encountered a lot more Republican opposition; it’s hard to imagine Nelson Rockefeller, Thomas E. Dewey or Dwight D. Eisenhower favoring so deep an assault on the social safety net. But there is little room for either moderation or compassion in the GOP of 2013.

American politics have evolved in such a way that in 2013, the United States has two main political parties: a very centrist, even center-right party (the Democrats) and a hard-right authoritarian party (the Republicans). GOP strategists may say they are the party of Abraham Lincoln, Dwight D. Eisenhower and Teddy Roosevelt, but none of those presidents would get very far in today’s GOP—certainly not at the national level. The GOP has become the party of Ted Cruz, Iowa Rep. Steve King, Rick Santorum and Virginia gubernatorial candidate Ken Cuccinelli. Here are 10 Republicans who would actually be hated if they were trying to make it in today's GOP.

1. Richard Nixon

The word “liberal” was seldom used in connection with Richard Nixon in the late 1960s or early '70s. Nixon was a paranoid Cold War anti-communist and uptight moralist who helped push the U.S. Supreme Court to the right, railed against pornography and defeated Democrat Hubert Humphrey in the presidential election of 1968 by helping to usher in the GOP’s “Southern strategy” (which was designed to win over racist Southern whites who had left the Democratic Party because of the civil rights movement and LBJ’s Great Society). Nevertheless, there are many things about Nixon that would make him persona non grata in the GOP of 2013.

Nixon strengthened social security benefits, supported elements of Franklin D. Roosevelt’s New Deal, and was instrumental in the creation of both the Environmental Protection Agency and the Occupational Safety and Health Administration in 1970. But perhaps Nixon’s greatest sin, in the minds of modern Republicans and the Tea Party, would be his support of universal healthcare. In 1974, Nixon and Democratic Sen. Ted Kennedy of Massachusetts worked out a healthcare reform deal. Kennedy, at first, proposed a single-payer healthcare system along the lines of Canada and the U.K., but when it became obvious he didn’t have the votes for that, the plan Kennedy and Nixon agreed upon would have been similar to the Affordable Care Act of 2010 but with more generous provisions. (“Nixoncare” was derailed by the Watergate scandal and Nixon’s resignation in 1974.) So when it came to healthcare reform, Nixon was to the left of President Barack Obama and way to the left of Paul Ryan or the Tea Party.

2. Earl Warren

To the Christian Right, the Warren Court of 1953-1969 went out of its way to erode family values in the United States. But Chief Justice Earl Warren was not a Democrat. He was a Republican ex-governor of California who was nominated to the U.S. Supreme Court by a Republican president: Dwight D. Eisenhower. The Warren Court handed down a lot of decisions that social conservatives detest, including the 1965 ruling in Griswold v. Connecticut (a right-to-privacy decision that struck down a Connecticut law forbidding the use of contraceptives by married couples), 1969’s Stanley v. Georgia decision (which said that mere possession of explicit porn is not a crime even if it is obscene) and the landmark 1957 ruling in Roth v. the United States. Roth established a whole new definition of obscenity that made it much more difficult to get an obscenity conviction for sexually explicit material. Christian Right activist Phyllis Schlafly, a major critic of the Roth decision, has complained that “the flood of pornography started with the Warren Court.”

These days, there is no way a Republican president would nominate someone as socially liberal as Earl Warren for the Supreme Court—and if a Republican who held Warren’s views ran for president, the Christian Right would see to it that he didn’t make it through the primary.

3. Dwight D. Eisenhower

Liz Cheney and many other neocons love to paint President Obama as a pacifist who is soft on national defense. This is ludicrous in light of the fact that Obama gave the order to kill Osama bin Laden in 2011 and ordered 17,000 more troops deployed in Afghanistan in 2009. But to neocons, the military-industrial complex can never be large enough or aggressive enough.

On January 17, 1961, it was none other than outgoing President Dwight D. Eisenhower who brought the term military-industrial complex into the public consciousness during his farewell speech. Eisenhower was hardly anti-military: he was a five-star general during World War II. But his words served as a warning against jingoism and a belligerent foreign policy. These days, no Republican would get very far in a presidential primary if he or she said what Eisenhower said 52 years ago: “We must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex. The potential for the disastrous rise of misplaced power exists, and will persist.”

4. Barry Goldwater

When Barry Goldwater ran for president against Democrat Lyndon B. Johnson in 1964, he suffered a landslide defeat: Johnson won 486 electoral votes, Goldwater a mere 52. A key factor in Goldwater’s defeat was the Johnson campaign’s ability to paint Goldwater as a warmonger who would get the U.S. into a nuclear war (which is ironic in light of how greatly LBJ escalated the country’s involvement in the Vietnam War). But even though Goldwater was considered an arch-conservative in the 1950s and '60s, he became quite critical of the GOP’s direction in the 1980s and '90s—and a key factor was his disdain for the Christian Right.

These days, it is impossible to get through a Republican presidential primary without pandering to the Christian Right, but when the Rev. Jerry Falwell felt that Sandra Day O’Connor was too socially liberal for the U.S. Supreme Court, Goldwater angrily responded, “Every good Christian ought to kick Falwell right in the ass.” Goldwater denounced Pat Robertson as a dangerous extremist, and he had no problem with gay men serving in the military. In 1996, Goldwater told Sen. Bob Dole: “We’re the new liberals of the Republican Party. Can you imagine that?”

5. Nelson Rockefeller

Nelson Rockefeller, who served as governor of New York State from 1959–'73 and as vice-president under Gerald Ford from 1974-'77, wasn’t perfect by any means. He supported New York State’s Rockefeller drug laws, which brought about draconian prison sentences for nonviolent drug offenses. But many of his positions—pro-New Deal, pro-choice, pro-Medicaid, pro-environment—resulted in Rockefeller being labeled the "leader of the northeastern wing of the Republican Party.” The term “Rockefeller Republican” came to symbolize Republicans who were liberal-leaning or at least centrist.

In the 1960s and '70s, some GOP strategists argued that a party that could accommodate politicians as different as Nelson Rockefeller and Barry Goldwater was healthy because of its diversity. But those days are long gone, and today, Rockefeller would have a very hard time getting ahead in a party where Michelle Bachmann and Steve King are considered role models.

6. Theodore Roosevelt

If Teddy Roosevelt were alive today, many of the corporatists in the modern GOP (and some corporatist Democrats as well) would accuse him of being anti-business and anti-capitalist. But Roosevelt was neither: he simply wanted corporations to behave more ethically. Roosevelt served as vice-president under President William McKinley and became president in 1901, when McKinley was assassinated; he went on to defeat Democrat Alton B. Parker in the election of 1904.

When Roosevelt was in the White House, he had a reputation for being pro-union and anti-monopoly and could be vehemently critical of large corporations. A strong proponent of anti-trust laws, he firmly believed that government should step in to break up corporations into smaller companies when they become monopolies. One can only imagine how livid Roosevelt would be over the bankster bailouts of 2008 and the phrase “too big to fail.” Indeed, many of Roosevelt’s statements about mega-corporations and monopolies sound a lot like what one would hear at an Occupy Wall Street demonstration.

8. Thomas E. Dewey

Before Nelson Rockefeller came to be recognized as the ideological leader of the liberal/centrist northeastern faction of the Republican Party, that position was unofficially held by Thomas E. Dewey (who served as governor of New York State from 1943-'54). There are some things about Dewey that the Republicans of 2013 might like: he was a strong supporter of the death penalty, and when he was a special prosecutor in New York City in the 1930s, Dewey aggressively shut down numerous houses of prostitution.

But for modern-day Republicans, Dewey’s unforgivable sin would be his support of parts of the New Deal. Dewey was an outspoken supporter of social security and unemployment insurance, and in a 1949 speech, he warned fellow Republicans that if they campaigned on shredding the social safety net, “you can bury the Republican Party as the deadest pigeon in the country.” Dewey ran for president twice, losing to FDR in 1944 and Harry Truman in 1948. But today, his chances of winning the GOP’s nomination in a presidential primary would be slim and none.

8. Gerald Ford

In 1974, many Democrats were furious with President Gerald Ford for granting Richard Nixon a full and unconditional pardon for his activities in the Watergate scandal. But there were many things about Ford (who lost to Democrat Jimmy Carter in the 1976 presidential race) that would make it impossible for him to win a GOP presidential primary today. Ford offered a conditional amnesty program for Americans who had dodged the draft during the Vietnam War, which wouldn’t sit well with today’s neocons. The Christian Right still hates Ford for his support of the Equal Rights Amendment and his position on abortion. Although Ford opposed the Roe v. Wade decision in 1973, he considered himself pro-choice and said he favored a “constitutional amendment that would permit each one of the 50 states to make the choice."

9. Raymond P. Shafer

When Richard Nixon asked Pennsylvania Gov. Raymond P. Shafer to be his running mate in the presidential election of 1968, his reasoning was clear: Shafer was known for being a northeastern Rockefeller Republican, and Nixon believed Shafer would bring some balance to the ticket and increase his chances of winning. But Shafer, a close ally of Nelson Rockefeller, declined Nixon’s offer (Spiro Agnew became his running mate instead).

The fact that Nixon sought a Rockefeller Republican as his running mate is quite a contrast to John McCain picking Sarah Palin in 2008 or Mitt Romney picking Paul Ryan in 2012. These days, someone as centrist as Shafer wouldn’t be considered for a GOP presidential ticket. Not only did Shafer support elements of the New Deal and call for more spending on public assistance in Pennsylvania, but in 1972, when Nixon appointed him as chairman of the National Commission on Marijuana and Drug Abuse, Shafer came out in support of marijuana decriminalization.

10. Arlen Specter

For many years, Arlen Specter was in an interesting position: he was a centrist Republican senator from Pennsylvania who was quite popular in overwhelmingly Democratic Philadelphia. Specter (who started out as a Democrat but was a Republican from 1965-2009 before becoming a Democrat again) was on friendly terms with many Democratic politicians, including former Philadelphia Mayor Ed Rendell.

But eventually, many of Specter’s positions—he was pro-choice, supported affirmative action and favored raising the minimum wage—made him much too moderate for his party. In 2004, he barely survived a GOP senatorial primary challenge from hard-right Pat Toomey, and in 2009, he returned to the Democratic Party rather than face Toomey in the 2010 primary (only to lose to Joe Sestak in the Democratic primary and watch Toomey narrowly defeat Sestak in the general election). Arlen Specter didn’t leave the Republican Party; the Republican Party left him.