Story highlights Hillary Clinton has been buoyed by the way Republicans have treated her, says David Gergen

Gergen: Republicans could well put the former first lady back in the White House

David Gergen is a senior political analyst for CNN and has been a White House adviser to four presidents. A graduate of Harvard Law School, he is a professor of public service and co-director of the Center for Public Leadership at the Harvard Kennedy School. Follow him on Twitter: @david_gergen. The opinions expressed in this commentary are his.

(CNN) For Hillary Clinton, Republicans have become the gift that keeps on giving. Mrs. Clinton owes much of her extraordinary comeback to her own abilities, but surely she must be grateful to the GOP as well. Never in modern times has a political party done so much to rehabilitate the leading presidential candidate in the other party.

The gifts have come in rapid succession:

-- The way Republicans have converted Donald Trump into GOP front-runner. For all for their misgivings about Clinton, Trump scares the bejesus out of millions of Americans. How long before we see sprouting of groups like "Republican Women for Hillary"?

-- The assertion by two Republican House members -- one the GOP majority leader -- that the Benghazi hearings were rigged to discredit Clinton.

-- The ouster of Speaker John Boehner by hard-right Republicans because he hasn't been sufficiently tough enough, a clear signal of who is running the House. Ask Mitt Romney how damaging it was to him to be seen as a captive of the far right.