Born in Hartford, Connecticut, McAuliffe graduated from Farmington High School in Farmington, Connecticut, where he was coached by Leo Pinsky and won the state championship in 1957. McAuliffe signed with the Detroit Tigers as an amateur free agent out of high school and spent three seasons in the Tigers' farm system. In 1960, he led the Southern League in runs (109), triples (21), and shortstop assists (430) while playing for the Knoxville Smokies. He was called up to the big leagues at the end of the 1960 season and made his major league debut on September 17, 1960.
In the 1961 and 1962 seasons, McAuliffe shifted between shortstop and second base before replacing Chico Fernandez as the Tigers starting shortstop from 1963–1966. Known for his wide-open batting stance and leg kick, McAuliffe never hit higher than .264 but was a significant contributor to the Tigers' offensive output in the 1960s. In 1965, he was the American League's starting shortstop in the All Star game, and he went 2-for-3 with a home run and 2 RBIs. In 1966, he finished the season ranked fourth in the league with a .373 on-base percentage and, fifth in the league with a .509 slugging percentage. After making the American League All Star team in 1965 and 1966 at shortstop, McAuliffe agreed to move to second base in 1967 to make room for Ray Oyler to take over at shortstop. Even with the move, McAuliffe was selected for his third consecutive All Star team in 1967. In 1967, McAuliffe was among the American League leaders in walks with 105 (3rd), 245 times on base (3rd), 7 triples (3rd), 92 runs (5th), 118 strikeouts (5th), 22 home runs (8th), and a .364 on-base percentage (9th).
In the Tigers' 1968 World Championship season, McAuliffe played a key role. He had a .344 on-base percentage, led the American League with 95 runs scored, and showed power with 50 extra base hits. He also tied a major league record by going the entire 1968 season without grounding into a double play and is the only American League player who has done so. McAuliffe also improved defensively in 1968, reducing his error total from 28 in 1967 to nine in 1968 and, finished second among American League second basemen in fielding percentage. He finished seventh in the 1968 American League Most Valuable Player Award voting, behind teammates Denny McLain, Bill Freehan, and Willie Horton.
On August 22, 1968, McAuliffe was involved in a brawl with Chicago White Sox pitcher Tommy John. After one pitch barely missed McAuliffe's head, and another was thrown behind him, McAuliffe charged the mound, drove his knee into John's shoulder and separated it. John was out for the season, and McAuliffe was suspended for five games. Interviewed 30 years later, McAuliffe was still convinced John was throwing at his head: "The first pitch at me was right at my head, and I mean right at my head. The catcher never laid any leather on it, and it hit the backstop. The next pitch, he spun me down, threw it behind me."
In the 1968 World Series, McAuliffe played all seven games at second base, scored 5 runs, and had 6 hits, 4 walks, 3 RBIs, and a home run. His steadying influence in the middle infield helped make it possible for manager Mayo Smith to take the radical step of playing center fielder Mickey Stanley at shortstop in the World Series in order to get a better bat in the lineup against the St. Louis Cardinals, led by Bob Gibson.
McAuliffe continued as the Tigers' starting second baseman through the 1973 season. In October 1973, the Tigers traded him to the Boston Red Sox for Ben Oglivie. McAuliffe hit only .210 in 100 games for the Red Sox in 1974. He began 1975 as the manager of Boston's Double-A farm team, the Bristol Red Sox, located in McAuliffe's native state of Connecticut. He guided Bristol into first place in the Eastern League, but was recalled to Boston in August to resume his playing career as a utility infielder. However, McAuliffe was released after playing only seven more games. His career ended on September 1, 1975, in a Yankees-Red Sox game. McAuliffe dropped an easy popup for an error. Later in the inning, McAuliffe's throw pulled Carl Yastrzemski off the bag. Though it was scored a single, the Boston fans booed McAuliffe. McAuliffe was left off Boston's post-season roster, and his major league career was over.
McAuliffe was among the American League leaders in triples eight times, and his ability to draw walks also increased his offensive output, ending his career with a .343 on-base percentage.
After retiring from baseball, McAuliffe owned a business that repaired and installed coin-operated washers and dryers for ten years, and also ran baseball schools. Bill James ranked McAuliffe 22nd all-time among second baseman in his Historical Baseball Abstract.
After a battle with Alzheimer's disease, McAuliffe died on May 13, 2016, at the age of 76, after suffering a stroke.