Hearts owner Ann Budge sees "no reason at all why" the Premiership leaders cannot maintain their title challenge.
The club are five points clear of second-placed Kilmarnock, and six ahead of champions Celtic - albeit having played a game more than the latter.
Hearts were beaten 3-0 by Brendan Rodgers' men in Sunday's Scottish League Cup semi-final at Murrayfield.
"I don't see why not, quite frankly," said Budge when asked if the Tynecastle side's challenge was sustainable.
"We're investing for the long term and if we keep doing that I see no reason at all why we can't keep fighting at the top of the league.
"We've been investing very heavily for the last four years, particularly in the academy and in the football operation."
Budge took over the Edinburgh outfit in 2014, bringing the club out of administration. Since then Hearts won the Championship in 2015, returned to European football by finishing third in the top flight the following year, and building a new main stand last year.
Regular payments from the Foundation of Hearts fans group have reached £8m and over 30,000 of the club's supporters attended the semi-final loss to Celtic.
"The supporters have been quite incredible," added Budge on BBC Radio 5live. "We are absolutely delighted to be doing what we're doing."