See also Pennsylvania Governor Martin Brumbaugh, Senator Albert Cummins of Iowa and former Vice President Charles Fairbanks were the main candidates.
See also United States Secretary of Commerce Herbert Hoover faced no major opposition in the primaries and easily won the general election against Al Smith.
At this point, a divide appeared in the Republican Party between the moderates and the conservatives, each claiming that only a candidate with their beliefs had a chance at beating Roosevelt as he ran for an unprecedented fourth term.
Among them were repeat candidates Douglas MacArthur, Senator Robert Taft, Governor Earl Warren, Businessman Riley A. Bender of Illinois, and the previous nominee Thomas Dewey.
See also Having suffered five consecutive losses, the Republican Party sought out a candidate who could appeal to voters all across the political spectrum, possibly through name recognition.
See also As a popular incumbent, with a strong economy and recent foreign policy victories including the Korean War, Eisenhower easily won his party's primaries in 1956 with little opposition, namely former candidate John Bricker from 1944, as well as Joe Foss of South Dakota and S.C. Arnold of Montana.
Thus, Nixon easily won the nomination, and selected longtime Eisenhower ally Henry Cabot Lodge Jr. as his running mate.
Thus, many in the Republican Party felt that they had a strong chance of winning, and turned to former Vice President and 1960 nominee Richard Nixon to run again.
Romney's record as Governor briefly elevated him with Nixon, but after a gaffe where he said he was "brainwashed" by the military into supporting the Vietnam War, he quickly lost his popularity and dropped out before the primaries even started.
Nixon's next challenge was the leader of the party's liberal wing, New York Governor Nelson Rockefeller, who briefly rose in popularity with his win in Massachusetts before fading in the polls as well.
Despite some supporters encouraging him to choose a former primary rival, such as Romney, as his running mate, Nixon ultimately chose Maryland Governor Spiro T. Agnew.
The Vietnam War was winding down and Nixon had achieved détente with China and the Soviet Union, as well as a stable economy at home and solidified victories in the Civil Rights Movement.
The sole delegate opposing his reelection was in support of Pete McCloskey, a representative from California, who ran on an anti-Vietnam War platform.
Ronald Reagan led the conservative wing of the party in condemning Ford's foreign policy in Vietnam, Eastern Europe and Panama.
Reagan gambled by announcing he would choose moderate Pennsylvania Senator Richard Schweiker as his running mate - the move ultimately backfired by alienating conservatives.
Ford narrowly won on the first ballot, and avoided the same mistake as Reagan by choosing conservative Kansas Senator Bob Dole as his running mate.
However, his campaign stumbled in the first few contests as it fell behind conservative insurgent Pat Buchanan in New Hampshire and publishing magnate Steve Forbes in Delaware and Arizona.
Bush easily won in Iowa but suffered a severe blow when Arizona Senator John McCain emerged as an insurgent candidate and defeated him in New Hampshire by 18 points.
Former New York City Mayor Rudy Giuliani was the frontrunner in the polls for most of 2007, but made a critical mistake by skipping the early primaries and staking his fortune on a win in Florida the week before Super Tuesday.
This backfired badly as John McCain, the runner-up of the 2000 primaries, whose campaign had been written off long before as a lost cause, surged suddenly in New Hampshire and rode a wave of momentum through South Carolina to defeat all other contenders in Florida.
Giuliani quickly dropped out and endorsed McCain, but former Massachusetts Governor Mitt Romney, a well-organized candidate who up to that point had won only his native Michigan and a couple minor caucus states, fought on.
McCain easily beat him on Super Tuesday, with assistance from former Arkansas Governor Mike Huckabee, a conservative contender who stole a few crucial Southern primaries, thus shutting Romney out.
Texas Representative Ron Paul, who had generated a lot of Internet buzz, but did not win a single contest, stayed in the race until the last primary votes were cast in June.
Ron Paul, who had been expected to perform much better than he did in 2008, only scored second-place finishes in contests such as New Hampshire and Virginia (where only he and Romney were on the ballot), and a narrow win in the popular vote in the U.S. Virgin Islands.
Romney maintained the upper hand throughout the primaries, winning most of the Super Tuesday contests and holding onto a wide lead in delegates.
Santorum's final efforts included a surprise victory in the Colorado caucuses, which Romney was expected to win, and narrow second-place performances in Michigan and Ohio.
Rubio managed only wins in Minnesota, Puerto Rico and the District of Columbia before losing his home state of Florida to Trump and being forced to drop out.
It was heavily speculated that Trump would not win the required number of delegates to clinch the nomination, resulting in a contested convention in Cleveland.
See also Former President Donald Trump easily defeated major candidates such as Nikki Haley and Ron DeSantis in order to be nominated for a nonconsecutive second term.