They can put the measure to a second vote to try and "override" the veto. If they succeed, the measure passes and becomes law, the presidents will or not. If they fail, the measure is dead - end of measure.
The veto.
VETO
Congress can pass a BILL over the President's veto making it a law.
If a US president vetoes a bill sent to him by the US Congress, the president may choose to veto the bill. In such a case, the bill is sent back to the congress. If the Congress can come up with a two thirds majority, then the bill must pass as law.
when two thirds of each House of Congress agree to do so
Congress can override the Presidents veto by a Supermajority Vote (2/3 of members)
A president's veto can be overridden by Congress with a 2/3 majority in the House. If it is a pocket veto though, the veto cannot be overridden.
This action is called an over-ride or over-riding of a veto.
Using the veto indicates that the President disagrees with Congress and that Congress was willing to pass a law they against the President's wishes.
Congressional Override
Overriding a veto
Yes