Appointed in May, McClaren has lost all of his first four league matches in charge in 2018-2019, including a humiliating 7-1 thrashing away to West Brom.
And after overseeing a 3-0 loss at home to Bristol City on Wednesday (AEST), the former England manager was asked if he is capable of reviving the team's fortunes.
"Yes," he replied.
"Absolutely. I knew the situation when I came in."
Of QPR's limited activity in the transfer market, McClaren added: "Believe me, if the owners could spend money - if they could - they would. But the restrictions are the restrictions."
And the ex-Middlesbrough, Twenty, Wolfsburg and Derby boss claimed to be unconcerned by the boos raining down from the home fans at Loftus Road.
"It is society now," he said.
"It's the reaction and this is normal. It's not been a good start. Am I determined to put this right? Yes.
"I knew this was a tough job and it wouldn't happen overnight. The message to the supporters, and it's a difficult one, is patience. We're in the loan market and free market and the owners are very supportive of that and that's the key message to the supporters, who might not think that.
"We've been working behind the scenes to bring signings in and we expect one or two before Saturday, but certainly the next 10 days are big, because we have talent and potential out there.
"At the present moment we're suffering. But I believe if we get the right players in we'll be OK."
QPR's next match is at home to Wigan Athletic on Sunday.