A group of tailer-park renters in Colorado say their landlord warned he would double their rent if U.S. President Donald Trump loses in the election.

The tenants are furious over a letter they received from their landlord that they say basically prods them to vote for Trump for president.

The letter promised no rent increases for two years if Trump is reelected, but threatened a drastic doubling of their rent if former vice president Joe Biden wins.

The residents emailed the letter to a news company and questioned whether the threat had any legal basis. The renters said despite the disclaimer of their landlord, sending the letter in the first place was tantamount to voter repression.

The letter stated in all-caps that: "IF the current President is reelected, WE WILL NOT RAISE THE RENT FOR AT LEAST 2 YEARS!" 9NEWS reported.

The letter - signed by trailer park landlord Bernie Pagel - adds that: "Everything will be increased. Like paying ALOT more in taxes, utilities, gasoline, groceries, new permits, fees and regulations...everything!"

To some people that sounds like an attempt to influence renters to vote for Trump rather than Biden, which can be considered as a form of voter intimidation.

The Office of the Colorado Secretary of State confirmed that they have received a complaint regarding the letter, and says they passed the information to the office of the Attorney General.

One of the residents, Cindy Marquez, told 9NEWS she has lived in the trailer park for two decades with her family and has never experienced such kind of political threat from her landlord. "It was very hurtful, you know? How could someone say something like that?" she said.

One of the key lines was the letter's closing part: "If Trump wins, we all win. If Biden wins, we all lose."