Brazil has made it clear that they oppose the sanctions, and Turkey, a close ally and trading partner of Iran, is also unlikely to support them. Lebanon too seems unable to support the sanctions, as the Iranian-backed Hezbollah is gaining increasing power in the lead up to what is expected to be another Israeli invasion.
The US can probably get enough votes to pass it even with this opposition, but a split vote would provide ample cover for either China or Russia (or both) to veto the sanctions outright.
Though Western nations are firmly on the US side on sanctions, Iran made a considerable win today when the Non-Aligned Movement (NAM), a bloc consisting of 118 developing nations, backed Iran’s right to a civilian nuclear program.
As Iran hasn´t done anything illegal, the UN sanctions are illegal.