However, to win the nomination outright Mr Santorum would have to claim
three-quarters of all the remaining delegates – a virtually impossible feat
– while Mr Romney needs less than half, a rate of victory that he has
consistently exceeded throughout the campaign.
Even if Mr Santorum does hold out in Pennsylvania he is likely to lose badly
in the forthcoming April 24 elections, when a series of moderate states like
New York and Connecticut are expected to give Mr Romney a string of
victories.
Ed Gillespie, a former party chairman, on Thursday joined Mr Romney’s campaign
in a sign of the Republican establishment’s growing impatience with the
drawn-out primary.
Mr Gillespie was also a former adviser to George W Bush, who has yet to
endorse a candidate even though his father, George Bush Snr, and younger
brother Jeb have backed Mr Romney.