Bob Dole was the republican candidate
In 2008, having fought against Hillary Clinton for the Democratic nomination, Barack Obama's opponent was Republican presidential candidate John McCain, whom he defeated to become president. In 2012, Mr. Obama had to fight against Republican presidential candidate Mitt Romney; once again, he was victorious, winning a second term as president.
In 2008, it was U.S. Senator John McCain of Arizona. In 2012, it was former Massachusetts governor Mitt Romney.
That candidate was US President William "Bill" Jefferson Clinton, in the year 1992.
In 1992 the incumbent president George H. W. Bush ran against Bill Clinton.
No, there were no significant challengers from within the Democratic Party to Bill Clinton during his reelection campaign for his second term as president in 1996. Clinton easily secured the Democratic nomination and ran unopposed within his own party.
NO- he was not a candidate for President. However, at the 1888 Republican Convention he did receive a vote for the Republican nomination.
He was the Democratic candidate in 1988, against Republican George H.W. Bush.
Bill Clinton's major opponents in 1992 were incumbent President George H. W. Bush and independent candidate Ross Perot. In 1996, his major opponents were Republican Party nominee Bob Dole and Reform Party nominee Ross Perot.
In a way this is what happened in 1912. Former President Theodore Roosevelt, who was elected as a Republican Vice President in 1900 and as a Republican President in 1904, tried to get the nomination in 1912, but when he failed to get it, he ran as a third party candidate against the incumbent Republican president William Howard Taft. Both were defeated by Democrat Woodrow Wilson.
The Republican candidate cannot start his presidential campaign until a Republican candidate is selected. The President probably won't start his campaign until he knows exactly who he will be running against.
The candidate for the Democratic-Republican Party in the election of 1796 was Thomas Jefferson. He ran against John Adams of the Federalist Party and ultimately became the vice-president after Adams won the presidency.