Conservatives have held on to power in two states in Germany's first regional elections since Angela Merkel took office in November.
The voter turnout in all three states was low
Ms Merkel's Christian Democrats retained control in Baden-Wuerttemberg in the south-west and in Saxony-Anhalt in the east.
Their coalition partners, the Social Democrats, held on to the state of Rhineland-Palatinate.
The two parties have been ruling together in an uneasy coalition.
Rhineland-Palatinate is the last big western state where the Social Democrats govern.
Voter turnout was low in all states, but particularly in Saxony-Anhalt with only 43% of potential voters taking part in the ballot.
Analysts note that the most significant result of Sunday's contests may be the ejection of the liberal Free Democrats as the junior coalition partner in all three states.
"The most important conclusion in my opinion is that protest parties from left and right failed to attract much support," Karl-Heinz Nassmacher, a political scientist at Oldenburg University, told Reuters news agency.