The Royal College of Nursing said it had received more than 100 letters of support from MPs after general secretary Peter Carter called for them to declare where they stand on the debate.
More than 200 MPs have also signed two early day motions calling for a fair pay deal for nurses, enough to make holding a debate in parliament possible.
Among those backing the motions are former health secretary Frank Dobson, shadow health secretary Andrew Lansley and Conservative leader David Cameron.
The RCN is preparing to ballot its 300,000 members on whether they would support a ballot for industrial action. The Royal College of Midwives also announced last week that it will ask the same question of its 37,000 members for the first time in its 125-year history.
Mr Carter said: 'It is clear from the response we have received so far that many MPs of all political persuasions believe the government is just plain wrong on this issue.'
RCM general secretary Dame Karlene Davis said: 'There is a groundswell of discontent among midwives on this issue.'