McLaren tireless in chase of Vettel; FORMULA ONE.
Button's stirring triumph in Canada 12 days ago suggested there is hope yet for all at McLaren, including Hamilton, following Vettel's runaway start to the campaign.
Six poles, five wins and two second-placed finishes have translated into a 60-point lead for Vettel over Button, with Hamilton fourth in the standings and 76 points adrift, after just seven races.
It remains to be seen whether Vettel can be overhauled throughout the remaining 12 grands prix, although forthcoming rule changes may yet play a role.
Regardless of how they unfold, Whitmarsh said: "Jenson's fantastic last-to-first result in Canada proved beyond doubt that, as a team, we never give up.
"That victory was a great fillip for the entire organisation and shows our tireless efforts to bring constant upgrades to the track are really paying off.
"As a team, it's particularly satisfying our upgrade 'hit-rate' has been successful and we've really been able to translate the results we've seen at the factory into concrete performance at the track.
"Again, that's the result of good teamwork and is what will successfully carry us through this championship fight.
"We're now into the heart of the season and need to ensure we're regularly delivering performance to the car.
"We've shown time and time again this is one of our key strengths, and I'm confident we can continue to deliver.
"For Valencia and beyond, our aim is clear: we want to win."
Ahead of Sunday's European Grand Prix in Valencia, where Hamilton has finished second on each of the three occasions the race has been run, Whitmarsh acknowledges Red Bull still have the edge.
"I think we go into the weekend feeling encouraged and motivated by our performance, although still realistic that Red Bull remains the pacesetter, particularly in qualifying," he said.
McLaren's Jenson Button