"Yes We Can"—Possibly derived from the United Farm Workers' slogan of 1972. The union's leader, Cesar Chavez, stated "Sí, se puede" ("Yes, it can be done"). Two years later, Philadelphia Phillies' second baseman Dave Cash came up with the "Yes We Can" slogan in support of his team, fighting for the pennant. Later, it appeared on the British children's TV show Bob the Builder, whose viewers heard the question "Can we fix it?" and the response "Yes we can!" Nevertheless, it is a very effective political slogan: positive and inclusive.
"Change We Can Believe In"—This slogan reinforces Obama's call to withdraw combat troops from Iraq, at first perhaps to differentiate his position from that of his Democratic primary opponents, particularly Hillary Clinton. Now it competes with McCain's call for "change."
"Reform, Prosperity, Peace"—Very similar to others in political history, including Wilson's “Peace With Honor” (U.S., 1916); the Bolsheviks' "Peace, Bread, and Land" (Russia, 1917); Cox's “Peace, Progress, Prosperity” (U.S., 1920); Willkie's “For Peace, Preparedness and Prosperity” (U.S., 1940); Truman’s “Secure the Peace” (U.S., 1948); Eisenhower's "Peace and Prosperity" (U.S., 1956); Koizumi's “Kaikaku” ["Reform"] (Japan, 2001). It attempts to communicate quite a lot: that McCain is for "change," "economic growth," and wants to get out of Iraq, but with "honor" (He could use Wilson's slogan, too).
"A Cause Greater Than Self"— a call to service for the country. This is a natural slogan for McCain, who has been in the U.S. Navy and Congress most of his adult life. In his memoir, McCain wrote, "Nothing in life is more liberating than to fight for a cause larger than yourself, something that encompasses you, but is not defined by your existence alone."
"Country First"—Partially a tactic to distance McCain from President Bush and the Republican Party; partially an attempt to stress McCain's heroism during the Vietnam War; partially a veiled effort to cast suspicion on Obama's patriotism.
"A Leader You Can Believe In"—McCain's campaign took the Obama slogan, changed it to emphasize a perceived strength for McCain, and made it, at the same time, into a negative attack on Obama.