Both Maine and Missouri were in the same position. They could not gain entrance to the union without the other. At the time, whenever a free state entered the union, a slave state had to enter also. So admitting Maine, meant admitting Missouri.
California is huge and the South wanted California to be part of the Confederacy.
The dispute was over whether Kansas would be admitted as a Slave State or a Free State. The Kansas-Nebraska Act allowed Kansas to enter as a Slave State if Nebraska entered as a Free one. The "bleeding" was from advocates on both sides trying to suppress the other by murder and terrorism.
The Missouri Compromise was not 1850 but 1820. It settled the issue of slavery in the new territories acquired from France in the Louisiana Purchase. The Compromise of 1850 was also to do with slavery/freedom in new territories, this time the ones acquired from Mexico.
Maine
Both Maine and Missouri were in the same position. They could not gain entrance to the union without the other. At the time, whenever a free state entered the union, a slave state had to enter also. So admitting Maine, meant admitting Missouri.
The phrasing of your question is a bit odd, but I interpret it as "Did the MO compromise allow 2 slave states into the Union?" If that was what you meant, the answer is no. The MO Compromise was made to keep the number senators from free and slave states equal. When it was made, the number was equal, so every slave state had to be admitted in a pair with a free state (and the other way around)(an example is the first pair that the compromise was used for: Maine was split from Massachusetts and admitted as a free state, and Missouri as shortly after admitted as a slave state; every state admitted between 1820 and 1850, when California was admitted alone as a free state (with a pro-slavery senator)). 2 slave states were never admitted at the same time, lest the compromise be broken. The MO Compromise was replaced with another deal in 1850.
The phrasing of your question is a bit odd, but I interpret it as "Did the MO compromise allow 2 slave states into the Union?" If that was what you meant, the answer is no. The MO Compromise was made to keep the number senators from free and slave states equal. When it was made, the number was equal, so every slave state had to be admitted in a pair with a free state (and the other way around)(an example is the first pair that the compromise was used for: Maine was split from Massachusetts and admitted as a free state, and Missouri as shortly after admitted as a slave state; every state admitted between 1820 and 1850, when California was admitted alone as a free state (with a pro-slavery senator)). 2 slave states were never admitted at the same time, lest the compromise be broken. The MO Compromise was replaced with another deal in 1850.
There was an issue over whether Missouri would become a slave or free state. It also raised the question of other new states being introduced into the United States. A compromise was made to allow Missouri to be admitted as a slave state and Kansas to be admitted as a free state.
California is huge and the South wanted California to be part of the Confederacy.
Maine was admitted as a U.S. state on March 19, 1820. It became the twentieth U.S. state. Augusta is the capital city in Maine. Maine is the blueberry capital of the U.S. producing 99% of U.S.'s blueberries. Maine also produces 50% of the lobster supply in the U.S.
It was the state that borders only one other New England state, Maine.
Because Senate was already 50% free states, 50% slave states, (11free/11slave) and adding Missouri as either a slave or free state would offset that balance and give more power to one side than to the other until Maine decided to want to be added as a free state, then Missouri came in as a slave state and therefore they wanted to keep the number even so the higher one wouldn't take over the other.
Before the Civil War, there was a perfect balance between "slave" states and "free" states. Neither side could budge the other, and no new states could be admitted to the Union without a vote of the Congress - more specifically, the Senate. So new states were admitted in pairs, one slave and one free, to preserve the balance. If one new "slave" state had been admitted to the Union, the majority of slave state senators would have been able to outvote the "free" state senators and admit more "slave" states. The balance was shattered when the southern states seceded from the United States, and the Civil War settled the issue - at the cost of a half-million dead.
Maine Maine
Maine.
It got California admitted as free soil, on condition that two other states could be admitted as slave-states.