Original sentence: The members of Congress would rather stonewall the proposal rather than to pass the new law.

Here is my corrected sentence:
3. The members of Congress would like to stonewall the proposal and not pass the new law.

5 answers

Why did you omit "rather?"
So the corrected sentence would be:
The members of Congress would rather stonewall the proposal and not pass the new law.
How about using "than" instead of "and"?
So the sentence would be:
The members of Congress would rather stonewall the proposal than not pass the new law.
Yes! :-)