A Panelbase study commissioned by the Yes Scotland campaign found that 48% of those questioned would be very or quite likely to back independence in September if they felt next year's UK election would result in a Conservative-led government, or another Conservative/Liberal Democrat coalition.
Almost two in five, 38%, said they would be unlikely to vote for independence if that were the case, while 13% said they did not know what way it would make them go.
Asked the same question about a Labour-led government, respondents were roughly evenly split in their views.
Some 42% said it would make them more likely to back independence, while 43% said it would make them unlikely to vote Yes in the ballot.
15% said they were in the "don't know" group.
Without reference to the UK election, the poll put the headline rate of support for independence at 40%, with the No camp at 45%. Again, 15% said they did not know.
Excluding "don't knows", the figure translates into 47% support for Yes and 53% for No.
A Yes Scotland spokesman said: "With the general poll figures showing Yes only needing another three points to reach 50%, people are even more likely to vote Yes when they think about who might form the next government at Westminster.
"Only the government of an independent Scotland will fully focus on Scottish needs and priorities."
A spokesman for the pro-UK group Better Together said: "On Saturday Alex Salmond told us the vote in September isn't about party politics, yet just one day later his campaign tells us it has everything to do with party politics. The utter hypocrisy of the mixed messages from the nationalists is the reason why the majority of people in Scotland are rejecting separation."
The poll was sampled among 1024 people from April 4-9.
It questioned people aged 16 and above living in Scotland. Young people under 18 years of age cannot vote in UK parliamentary elections.