Sinodinos says marriage change likely

A national vote on same-sex marriage is likely to succeed, says senior Liberal Arthur Sinodinos.

Arthur Sinodinos says the government's budget review is a breakthrough in the tax debate. (AAP)

Liberal senator Arthur Sinodinos says a national vote is likely to land in favour of same-sex marriage.

Prime Minister Tony Abbott has pledged to hold a plebiscite or referendum next term on changing marriage laws, which Senator Sinodinos said would give a "strong indication" what Australians wanted.

"The odds are, that's where we will end up," Senator Sinodinos said of a majority "yes" vote.