Rangers overcame boss Neil Warnock's former club Crystal Palace on Saturday to extend their advantage at the top to 10 points.
And Smith, who started in the 2-1 victory after returning from a hamstring injury, is adamant that they will not be caught.
"I'm very confident the boys won't blow it. We're trying not to look too far in front, and we've been like that all season," he told the Ealing Gazette.
"If we win our home games and pick up a couple away from home that should be enough."
The London club are still waiting to find out what their punishment will be after being charged with breaching the rules on third-party ownership in relation to Alejandro Faurlin.
Source: PA
Source: PA