Some of the biggest campaign contributions to the two candidates squaring off to be the next Las Vegas mayor are from a casino located 11 miles outside the city limits.

South Point Casino Resort is closer in proximity to Henderson than it is to Las Vegas City Hall.

But that didn’t stop owner Michael Gaughan from embarking on an unwritten rule among old-school Las Vegas casino executives: donate to both candidates.

Gaughan, through South Point, donated $10,000 — the maximum campaign contribution possible — to former Rep. Shelley Berkley (D-NV) and Las Vegas City Councilwoman Victoria Seaman, according to campaign finance reports filed with the Nevada Secretary of State’s Office.